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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.

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.

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.

This paper aims to determine the knowledge and attitudes of the physicians regarding human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS), to emphasize that these patients exist and they will exist in the future and to raise awareness so as to prevent that their rights to treatment are revoked.

The survey was conducted via a link sent through an online system. Random physicians from 81 cities of the country were invited to the survey. The survey has 41 questions regarding knowledge and attitudes in total, including epidemiological information such as age, gender and title.

A total of 3,107 physicians has voluntarily participated in the study. In total, 2,195 (70.7%) are internal physicians and 912 (29.3%) are surgical physicians among the participant physicians. In total, 1,452 (46.7%) of the participants are specialist physicians, 608 (19.6%) of the participants are practising physician and the rest of it is physician assistants, academicians and dentists, respectively.

In this study, it has been found out that the physicians have a lack of knowledge on HIV/AIDS and they adopt a discriminatory attitude towards HIV-positive persons. HIV-positive patients who are exposed to discrimination and scared of being uncovered refrain from applying to hospitals for treatment, which puts public health into jeopardy due to the high viral load and these patients are faced with difficulties in coping with both medical and emotional load of the disease.

This paper aims to concentrate on recent innovations in flexible wearable sensor technology tailored for monitoring vital signals within the contexts of wearable sensors and systems developed specifically for monitoring health and fitness metrics.

In recent decades, wearable sensors for monitoring vital signals in sports and health have advanced greatly. Vital signals include electrocardiogram, electroencephalogram, electromyography, inertial data, body motions, cardiac rate and bodily fluids like blood and sweating, making them a good choice for sensing devices.

This report reviewed reputable journal articles on wearable sensors for vital signal monitoring, focusing on multimode and integrated multi-dimensional capabilities like structure, accuracy and nature of the devices, which may offer a more versatile and comprehensive solution.

The paper provides essential information on the present obstacles and challenges in this domain and provide a glimpse into the future directions of wearable sensors for the detection of these crucial signals. Importantly, it is evident that the integration of modern fabricating techniques, stretchable electronic devices, the Internet of Things and the application of artificial intelligence algorithms has significantly improved the capacity to efficiently monitor and leverage these signals for human health monitoring, including disease prediction.

In repetitive projects, repetition offers more possibilities for activity scheduling at the sub-activity level. However, existing resource-constrained repetitive scheduling problem (RCRSP) models assume that there is only one sequence in performing the sub-activities of each activity, resulting in an inefficient resource allocation. This paper proposes a novel repetitive scheduling model for solving RCRSP with soft logic.

In this paper, a constraint programming model is developed to solve the RCRSP using soft logic, aiming at the possible relationship between parallel execution, orderly execution or partial parallel and partial orderly execution of different sub activities of the same activity in repetitive projects. The proposed model integrated crew assignment strategies and allowed continuous or fragmented execution.

When solving RCRSP, it is necessary to take soft logic into account. If managers only consider the fixed logic between sub-activities, they are likely to develop a delayed schedule. The practicality and effectiveness of the model were verified by a housing project based on eight different scenarios. The results showed that the constraint programming model outperformed its equivalent mathematical model in terms of solving speed and solution quality.

Available studies assume a fixed logic between sub-activities of the same activity in repetitive projects. However, there is no fixed construction sequence between sub-activities for some projects, e.g. hotel renovation projects. Therefore, this paper considers the soft logic relationship between sub-activities and investigates how to make the objective optimal without violating the resource availability constraint.

Given the progressive rise of online health communities (OHC) that have predominantly changed health delivery services, healthcare organizations still face tremendous challenges of low patient participation and lack of high-quality contribution to OHC. Prior scholars indicated that inducing patient value co-creation behavior (VCB) is substantially beneficial for the sustainable growth of OHCs. However, what drives patients' behavior to co-create value is still unknown. To fill this important gap, this study used the service-dominant logic of value co-creation theory and face (mianzi in Chinese) literature to discover how patient co-creation attitude (CA) affects patient VCB. Also, this study aimed to explore the joint mechanism of how face gain (FG) and face loss (FL) impact patients' VCB in OHCs.

The survey data of 322 patients actively using OHC in China were analyzed via partial least squares structural equation model (PLS-SEM) and fuzzy set qualitative comparative analysis (fsQCA).

The results revealed that patient CA positively influences VCB, that is participation behavior (PB) and citizenship behavior (CB). Face gain (FG) strengthens the impact of CA and patient PB and CB, whereas face loss (FL) weakens the impact of CA and patient PB and CB. Furthermore, the fsQCA findings signify the robustness of the study model.

This study explores the multifaceted mechanism of patient value co-creation in OHC and discloses the crucial role of face for the first time. Further, the novel findings of this study provide a robust framework for advancing the understanding of important drivers of patient VCBs that significantly helps healthcare service providers and OHC managers to sustain OHCs.