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Intelligent tutoring systems (ITS) are a supplemental educational tool that offers great benefits to students and teachers. The systems are designed to focus on an individual’s characteristics, needs and preferences in an effort to improve student outcomes. Despite the potential benefits of such systems, little work has been done to investigate the impact of ITS on users. To provide a more nuanced understanding of the effectiveness of ITS, the purpose of this paper is to explore the role of several ITS parameters (i.e. knowledge, system, service quality and task–technology fit (TTF)) in motivating, satisfying and helping students to improve their learning performance.

Data were obtained from students who used ITS, and a structural equation modeling was deployed to analyze the data.

Data analysis revealed that the quality of knowledge, system and service directly impacted satisfaction and improved TTF for ITS. It was found that TTF and student satisfaction with ITS did not generate higher learning performance. However, student satisfaction with ITS did improve learning motivation and resulted in superior learning performance. Data suggest this is due to students receiving constant and constructive feedback while simultaneously collaborating with their peers and teachers.

This study verifies that there was a need to assess the benefits of ITS. Based on the study’s findings, theoretical and practical implications are proposed.

This paper aims to achieve two main objectives. First, to introduce to the literature a new versatile active building block, namely, voltage differencing differential voltage current conveyor (VD-DVCC) for analog signal processing applications. Second, to design a novel electronically tunable mixed-mode universal filter. The designed filter provides low-pass, high-pass, band-pass, band-reject and all-pass responses in voltage-mode (VM), current-mode (CM), trans-impedance-mode (TIM) and trans-admittance-mode (TAM).

The proposed filter uses two VD-DVCCs, three resistors and two capacitors. All the capacitors used are grounded, which is advantageous from the monolithic integration point of view. The VD-DVCC is designed and validated in Cadence software using CMOS 0.18 µm process design kit from Silterra Malaysia at a supply voltage of ±1 V.

The proposed novel filter enjoys many attractive features including as follows: the ability to operate in all four modes, no requirement of capacitive matching, tunability of quality factor (Q) independent of pole frequency, availability of both inverting and non-inverting outputs for VM and TIM mode, high output impedance explicit current output for CM and TAM, no requirement for double/negative input signals (voltage/current) for response realization and low active and passive sensitivities. The filter is designed for a pole frequency of 5.305 MHz. The obtained results bear a close resemblance with the theoretical findings.

The proposed novel filter structure requires a minimum number of active and passive components and provides operation in all four operating modes. The filter will find application in structures of mixed-mode systems.

This study aims to investigate the ammonia-sensing performance of polyaniline/polyethylene oxide (PANI/PEO) and polyaniline/polyethylene oxide/zinc oxide (PANI/PEO-ZnO) composite nanofibers at room temperature.

Gas sensor structures were fabricated using microfabrication techniques. First, onto the SiO₂ wafer, gold electrodes were fabricated via thermal evaporation. PANI/PEO nanofibers were produced by the electrospinning method, and the ZnO layer was deposited by using radio frequency (RF) magnetron sputtering on the electrospun nanofibers as a sensing layer. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray diffraction were performed to characterize the analysis of nanofibers. After all, gas sensing analysis of PANI/PEO and PANI/PEO/ZnO nanofibers was conducted using an experimental setup at room temperature conditions. Furthermore, the impact of humidity (17%–90% RH) on the sensor resistance was actively investigated.

FTIR analysis confirms the presence of functional groups of PANI, PEO and ZnO in nanofiber structure. SEM micrographs demonstrate beads-free, thinner and smooth nanofibers with ZnO contribution to electrospun PANI/PEO nanofibers. Moreover, according to the gas sensing results, the PANI/PEO nanofibers exhibit 115 s and 457 s response time and recovery time, respectively. However, the PANI/PEO/ZnO nanofibers exhibit 245 s and 153 s response time and recovery time, respectively. PANI/PEO/MOx composite nanofibers ensure stability to the NH₃ gas owing to the high surface/volume ratio and decrease in the humidity dependence of gas sensors, making gas sensors more stable to the environment.

In this study, ZnO was deposited via RF magnetron sputtering techniques on PANI/PEO nanofibers as a different approach instead of in situ polymerization to investigate and enhance the sensor response and recovery time of the PANI/PEO/ZnO and PANI/PEO composite nanofibers to ammonia. These results indicated that ZnO can enhance the sensing properties of conductive polymer-based resistive sensors.

The purpose of this paper is to evaluate the effect of fasting on anthropometry and body composition in fasting obese and non‐obese subjects.

In total, 25 volunteers (male and female) were recruited during Ramadan. Age, sex, weight, height, waist and hip circumference and menstrual cycle status (in case of females) were recorded on day 1, and on day 21 weight and waist and hip circumference were also recorded. Similarly, bioelectrical impedance analysis (BIA) was performed on days 1 and 21 for the assessment of changes in body composition. From weight and height, basal metabolic Index (BMI) was determined. Waist‐hip ratio was determined from the waist and hip circumferences.

Weight was significantly (p<0.001) reduced in obese individuals on day 21 and accompanied by significant (p<0.01) reduction in waist hip ratios. BIA showed no significant change in the intra or extra cellular water. However, there has been shift of water between the two compartments and there was a strong positive correlation (r=0.9) between the fat free mass and total body water and negative association (r=−0.9) with total body water.

This study indicates that fasting could be a useful tool for the management of body weight without having a major shift in the body composition.

This paper aims to study inhibitory effect of 4-aminothiophenol on the corrosion of mild steel (MS) in 0.5 M HCl.

In this study, electrochemical experiments, quantum chemical calculations, potentiodynamic measurements, linear polarization resistance and scanning electron microscopy were used.

The experimental results suggest that this compound is efficient corrosion inhibitor and the inhibition efficiencies increase with increasing their (from 0.5 to 10.0 mM.) concentrations. This reveals that inhibitive actions of inhibitors were mainly due to adsorption on mild steel surface. The adsorption of these inhibitors was found to obey Langmuir adsorption model. The computed quantum chemical features show good correlation with empirical inhibition efficiencies.

The 4-aminothiophenol is suitable inhibitor for application in closed-circuit systems against corrosion. The study is original and has great impact in industrial area. The obtained theoretical results have been adapted with the experimental data.

This chapter of the book aims to introduce multiobjective linear programming (MLP) as an optimum tool to find the best quality engineering techniques (QET) in the main domains of supply chain management (SCM). The importance of finding the best quality techniques in SCM elements in the shortest possible time and at the least cost allows all organizations to increase the power of experts’ analysis in supply chain network (SCN) data under cost-effective conditions. In other words, this chapter aims to introduce an operations research model by presenting MLP for obtaining the best QET in the main domains of SCM. MLP is one of the most determinative tools in this chapter that can provide a competitive advantage. Under goal and system constraints, the most challenging task for decision-makers (DMs) is to decide which components to fund and at what levels. The definition of a comprehensive target value among the required goals and determining system constraints is the strength of this chapter. Therefore, this chapter can guide the readers to extract the best statistical and non-statistical techniques with the application of an operations research model through MLP in supply chain elements and shows a new innovation of the effective application of operations research approach in this field. The analytic hierarchy process (AHP) is a supplemental tool in this chapter to facilitate the relevant decision-making process.

This article presents an exploratory, narrative review on job ads research. It aims to explore the key features of job ads that have been investigated in previous researches; the way these features have been investigated; and to draw important lessons that those studies teach us about the impact of job ad features on the target population.

In this study, the scoping-review procedure is applied. Its systematic procedure enables scholars to provide a broad overview of a topic, map the key concepts underpinning a research area, clarify the conceptual boundaries of a topic, and also to incorporate a numerical summary and qualitative thematic analysis. The review was conducted based on a systematic study of 243 peer-reviewed articles and publications in the grey literature.

The findings show that seven job ad features seem to have important impacts on (potential) applicants, which we illustrate as a know-how framework. Eight main theories are used, and a wide array of research methods are applied. However, the study concludes that after more than four decades of research, there is still a limited understanding about the concrete effects of job ad features.

This paper synthesizes the existing knowledge, answers three exploratory questions regarding job ad features and draws theoretical and practical lessons from previous studies. In the interest of conducting future studies and providing a research agenda, a typology of theoretical perspectives for the study of job ads is also presented. The article also presents lessons for practitioners by providing a know-how framework on the usage of job ads.

Despite promising conceptual developments in value co-creation behaviors, the scholarly attention afforded to the importance of the university website features in strengthening the university brand image and reputation through students’ value co-creation behaviors is limited. University website features are conceptualized as a hierarchical construct with three dimensions: usability, availability and information. This study aims to investigate the effect of university website features and value co-creation behaviors of students on promoting brand image and brand reputation at Islamic Azad University in Iran.

This study is quantitative. Using convenience sampling techniques, a responsive group of 384 students was chosen from the Islamic Azad University of Tehran in Iran. Survey methods were used for data collection. Partial least squares structural equation modeling was used to test the derived hypotheses.

The findings of this study indicated that website features have a positive effect on fostering value co-creation behaviors (participation and citizenship behavior), and participation behavior, in turn, improves university brand image and reputation. At the same time, among value co-creation behaviors, citizenship behavior has no impact on the university’s brand image. Finally, the brand image formed through website features and participation behavior positively affects brand reputation.

This study was conducted in the higher education (HE) sector in one cosmopolitan Iranian city (i.e. Tehran), to which Iranians from other cities travel for studying. Thus, the results of this survey include a variety of subcultures. In the future, a study that incorporates all major metropolitan cities of Iran may increase the generalizability of the findings. Unrelated to the purpose of this study, a future research study may extend the currently studied geographical dimensions and examine the antecedents of university brand reputation across different nations using a cross-cultural approach.

Pragmatically, the findings of this study urge university policymakers, information technology managers and marketers to consider the university website’s unique role in assisting co-creation behavior, which in turn promotes university brand image and reputation in the HE market. One of the ways to assess a university’s brand image and reputation is through the university ranking system. Ascending the ranking system can allow a university to attract qualified students.

These findings contribute to the marketing literature by empirically validating the three elements in the website features construct, providing intelligence on how website features can drive value co-creation behaviors, brand image and reputation. Also, results revealed that the brand image of universities positively affects brand reputation. This study highlights the importance of national and international rankings of universities and students’ sensitivity to such rankings. Undoubtedly, this is evident in Iranian students’ behavior in selecting their university.