130 research outputs found
Deciphering the Nexus: Blockchain-Smart Contracts and Their Transformative Potential in the Construction Industry
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
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
L'impact de la volatilité des taux de change sur le commerce international : essai de validation empirique désagrégées des exportations sectorielles canadiennes vers les États-Unis via une approche d'estimation VAR
La présente étude offre un panorama sur les interactions et les liens qui existent entre la volatilité des taux de change et les échanges internationaux. L’objectif de ce travail est donc de présenter théoriquement cette relation, puis d’examiner empiriquement l’existence de cette relation de causalité entre le commerce international et la variabilité des taux de change. La littérature portant sur la question se considère dans l'ensemble comme contradictoire et supporte plusieurs controverses qui ne nous permettent pas de conclure clairement quant à la relation en question. Nous essayerons de pousser ces recherches un peu plus loin en réexaminant cette évidence pour le canada et en offrant une investigation empirique sur l’existence éventuelle d'un impact significatif de la volatilité sur les flux désagrégées des exportations sectoriels du canada vers son partenaire, les États-Unis. Nous y examinons la réponse empirique de 5 secteurs d’exportations canadiennes aux variations du taux de change réel effectif entre le canada et les États- Unis.
Toutefois, nos résultats obtenus ne nous permettent pas de conclure quant à la significativité relative d’un impact de volatilité de taux de change sur les exportations sectoriels désagrégées destinées aux États-Unis. Dans l’ensemble, même si on admet que les signe des coefficients estimés de la variable de risque dans chaque secteur est négatif, nous arrivons à la conclusion que la volatilité ne semble pas avoir un impact statistiquement significatif sur le volume réelle des exportations du Canada vers les États-Unis.This study provides an overview on the interactions and linkages between the volatility of exchange rates and international trade. The objective of this work is to present this relationship theoretically and examine, empirically the existence of this causal relationship between international trade and exchange rate variability. The literature on the subject considers himself across as contradictory and supports several controversies that do not allow the clear conclusion about the relationship in question.
We try to push this research a step further by reviewing the evidence for Canada and providing an empirical investigation on the possible existence of a significant impact of volatility on sectoral disaggregated flows of Canadian exports to its trading partner, the United States. We empirically examine the response of five sectors of Canadian exports to changes in real effective exchange rate between Canada and the United States.
However, our results do not allow us to conclude about the significance of an impact on volatility of exchange rates on disaggregated sectoral exports to United States. Overall, even if we admit that the sign of the estimated coefficients of the exchange risk variable in each sector is negative, we reach the conclusion that the volatility does not seem to have a statistically significant impact on the real volume of exports from Canada to the United States
Shear Behavior of High-Performance Reinforced Concrete Beams
High-performance concrete (HPC) is one of such new material that has a major improvement over conventional concrete; however, its behavior has to be fully understood. This paper presents experimental and numerical investigations in order to study the shear behavior of high-performance reinforced concrete beams. Four RC-HPC beams were tested experimentally in order to study the effect of the existence of web reinforcement and bar diameter of the web reinforcement as well as the amount of the tensile longitudinal steel bars on the shear behavior. Test results showed higher values of shear strength, stiffness, ductility and controlled the concrete cracking behavior due to the presence of stirrups. The ultimate load for beam having shear reinforcement of 6 mm diameter increased by about 16% compared to that of control beam BI-1 without shear reinforcement, while, that increase reached up to 34% for beam having 8 mm diameter web reinforcement. Besides, the numerical modeling enabled to capture satisfactory the behavior of HPC beam so that it can be used to study the effect of more parameters on the behavior of HPC beams
Shear Behavior of High-Performance Reinforced Concrete Beams
High-performance concrete (HPC) is one of such new material that has a major improvement over conventional concrete; however, its behavior has to be fully understood. This paper presents experimental and numerical investigations in order to study the shear behavior of high-performance reinforced concrete beams. Four RC-HPC beams were tested experimentally in order to study the effect of the existence of web reinforcement and bar diameter of the web reinforcement as well as the amount of the tensile longitudinal steel bars on the shear behavior. Test results showed higher values of shear strength, stiffness, ductility and controlled the concrete cracking behavior due to the presence of stirrups. The ultimate load for beam having shear reinforcement of 6 mm diameter increased by about 16% compared to that of control beam BI-1 without shear reinforcement, while, that increase reached up to 34% for beam having 8 mm diameter web reinforcement. Besides, the numerical modeling enabled to capture satisfactory the behavior of HPC beam so that it can be used to study the effect of more parameters on the behavior of HPC beams
Tree Growth Algorithm for Parameter Identification of Proton Exchange Membrane Fuel Cell Models
Demonstrating an accurate mathematical model is a mandatory issue for realistic simulation, optimization and performance evaluation of proton exchange membrane fuel cells (PEMFCs). The main goal of this study is to demonstrate a precise mathematical model of PEMFCs through estimating the optimal values of the unknown parameters of these cells. In this paper, an efficient optimization technique, namely, Tree Growth Algorithm (TGA) is applied for extracting the optimal parameters of different PEMFC stacks. The total of the squared deviations (TSD) between the experimentally measured data and the estimated ones is adopted as the objective function. The effectiveness of the developed parameter identification algorithm is validated through four case studies of commercial PEMFC stacks under various operating conditions. Moreover, comprehensive comparisons with other optimization algorithms under the same study cases are demonstrated. Statistical analysis is presented to evaluate the accuracy and reliability of the developed algorithm in solving the studied optimization problem
Optimization of nanostructured/nano sized rice husk ash preparation
تم تطوير إجراء لإنتاج رماد قشر الأرز. وقد تم دراسة تأثير العوامل المؤثرة على إنتاجية وخصائص السيليكا غير المتبلورة وهذه العوامل هى الكمية الابتدائية لقشر الأرز و ظروف الاحتراق و التقليب . تم التوصل إلى أن أفضل كمية كانت 20 غراما في الدقيقة في صحن تبخر خزفي بحجم 125 مل يحترق لمدة ساعتين عند درجة حرارة 700 درجة مئوية ، مع تبريد على ثلاث فترات أثناء الاحتراق لإنتاج السليكا عند أقل فقد عند الاشتعال وقد وجد أيضا أن فترات التبريد تلعب دوراَ هاماَ فى تباين حجم الهيكل النانوي وتوزيع شكل الجسيمات. بالاضافة إلى أنه لم يتم العثور على مراحل بلورية في رماد قشر الأرز في جميع الحالات.The objective of the study is developing a procedure for production and characterization of rice husk ash (RHA). The effects of rice husk (RH) amount, burning/cooling conditions combined with stirring on producing of RHA with amorphous silica, highest SiO2, lowest loss on ignition (LOI), uniform particle shape distribution and nano structured size have been studied. It is concluded that the best amount is 20 g RH in 125 ml evaporating dish Porcelain with burning for 2 h at temperature 700 °C combined with cooling three times during burning to produce RHA with amorphous silica, SiO2 90.78% and LOI 1.73%. On the other hand, cooling and stirring times affect the variation of nano structured size and particle shape distribution. However, no crystalline phases were found in RHA in all cases. Results proved that the Attritor ball mill was more suitable than vibration disk mill for pulverizing nano structured RHA with 50% of particle size (D50) lower than 45 mm and 99 % of particle size (D99) lower than 144 mm to nanosized RHA with D50 lower than 36 nm and D99 lower than 57 nm by grinding time 8.16 min to every 1 g RHA without changes in morphousity of silica
Measuring sociocultural engagement of health professions education students:a psychometric study
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
Measuring sociocultural engagement of health professions education students:a psychometric study
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
Evaluation of Color Difference and Translucency of Modified PEEK Restorations Veneered with Different Veneering Materials Before and After Thermal Cycling
Objective: The aim of this study was to investigate the effect of different PEEK veneering materials, as well as thermocycling on the color difference (ΔE) and the translucency parameter (TP) of modified PEEK veneered restorations.
Materials and Methods: Thirty disc shaped specimens of veneered BioHPP (1.5 mm X 12 mm) were randomly divided into three groups (n=10) based on the type of the veneering material. Group (A): Discs veneered with CAD milled Lithium Disilicate, group (B): Discs veneered with pre-cured milled composite, and group (C): Discs veneered with conventional light cured composite. CIELab values were calculated for all specimens over white and black backgrounds using a laboratory spectrophotometer and then (ΔE) and (TP) were calculated. Specimens were subjected to thermal cycling, after which the same procedure for calculating (ΔE) and (TP) was repeated.
Results: Repeated measures ANOVA showed that both the veneering material, and thermocycling had a statistically significant effect on mean ΔE, and on (TP) (P-value
Conclusions: All veneering techniques rendered an amount of color difference that was clinically unacceptable, as well as displaying much lower translucency levels than that of natural enamel and dentine
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