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This paper aims to develop a numerical model of bead spreading architecture of a viscous polymer in fused filament fabrication (FFF) process with different nozzle geometry. This paper also focuses on the manufacturing feasibility of the nozzles and 3D printing of the molten beads using the developed nozzles.

The flow of a highly viscous polymer from a nozzle, the melt expansion in free space and the deposition of the melt on a moving platform are captured using the FLUENT volume of fluid (VOF) method based computational fluid dynamics code. The free surface motion of the material is captured in VOF, which is governed by the hydrodynamics of the two-phase flow. The phases involved in the numerical model are liquid polymer and air. A laminar, non-Newtonian and non-isothermal flow is assumed. Under such assumptions, the spreading characteristic of the polymer is simulated with different nozzle-exit geometries. The governing equations are solved on a regular stationary grid following a transient algorithm, where the boundary between the polymer and the air is tracked by piecewise linear interface construction (PLIC) to reconstruct the free surface. The prototype nozzles were also manufactured, and the deposition of the molten beads on a flatbed was performed using a commercial 3D printer. The deposited bead cross-sections were examined through optical microscopic examination, and the cross-sectional profiles were compared with those obtained in the numerical simulations.

The numerical model successfully predicted the spreading characteristics and the cross-sectional shape of the extruded bead. The cross-sectional shape of the bead varied from elliptical (with circular nozzle) to trapezoidal (with square and star nozzles) where the top and bottom surfaces are significantly flattened (which is desirable to reduce the void spaces in the cross-section). The numerical model yielded a good approximation of the bead cross-section, capturing most of the geometric features of the bead with a reasonable qualitative agreement compared to the experiment. The quantitative comparison of the cross-sectional profiles against experimental observation also indicated a favorable agreement. The significant improvement observed in the bead cross-section with the square and star nozzles is the flattening of the surfaces.

The developed numerical algorithm attempts to address the fundamental challenge of voids and bonding in the FFF process. It presents a new approach to increase the inter-bead bonding and reduce the inter-bead voids in 3D printing of polymers by modifying the bead cross-sectional shape through the modification of nozzle exit-geometry. The change in bead cross-sectional shape from elliptical (circular) to trapezoidal (square and star) cross-section is supposed to increase the contact surface area and inter-bead bonding while in contact with adjacent beads.

Pakistan's present war against extremists has many folds and sheds. The country's initial participation in the Afghan War in 1979 later gave birth to different extremist trends in the country. State patronage of the extremist Wahabi Islamists during the Afghan jihad opened another conflict in Pakistan, and things became more complicated. The combination of external and internal factors gave birth to the worst kind of conflict, which now has not only become dangerous for the country's own existence but also a major threat for global peace. The Afghan jihad initially started as a war against Soviet occupation and later became the hub of global jihad-war against infidels.

This chapter analyzes how external factors promoted internal contradictions in Pakistan due to which the country became not only an exporter of jihadis for the world but also the worst kind of sectarian conflicts, including. Shia–Sunni, Deobandi–Wahabi clashes, entered into in the past two decades. Such a strong link exists with Pakistan's official support to global jihad. Draft sectarian groups now head to head with their opponents have killed thousands of members of rival sectors, have strong support from external sympathizers, and have spread in the country. The well planned terrorist activities of these groups reflect the fact that support to these groups in the past is now leading to a severe crisis in Pakistan. The nexuses of these indigenous extremists like Lashkar-e-Jhangvi, Lashkar-e-Taiba, Tehrik-e-Taliban Pakistan, and Hizb-ul-Mujahideen with external terrorist organizations like Al-Qaeda, the Taliban, and Islamic Movement of Uzbekistan of Tahir Yuldasher Chechen Guerilla War has led to several bloody clashes in the country and outside.

Attaining equality between women and men and eliminating all forms of discrimination are fundamental human rights and United Nations values. Nevertheless, women globally suffer violations of their human rights throughout their lives. This necessitates investigation of the attitude that people hold towards women empowerment, which is defined as their ability to practice their rights, freedom and attain resources within a framework of gender inequality. The purpose of this study is to develop an instrument to measure attitudes regarding women’s empowerment, which can develop better understanding and future interventions to counter these negative attitudes for better social and health care, including mental and physical health.

The factorial structure, reliability, content validity and impact of gender on factor structure of scale were examined among university students (N = 500) in study with male (n = 180) and female (n = 320) population.

Exploratory factor analysis using direct oblimin method based on principal component analysis indicated a three-factor, 16-item scale including subscales of personal freedom; equal rights and women empowerment-related fears. Instrument exhibited decent reliability (0.80) and content validity in both male and female university students with a t = −7.64, p = 0.00, suggesting a highly significant difference between the two genders on the developed scale.

The major limitation was that the sample was obtained from student population; therefore, it will not be entirely correct to generalize it to the whole population of Pakistan. Similarly, there are issues regarding the availability of students because of a busy schedule or not having interest to take part in the study that led to variance in the sample. Lastly, the current scale is developed based on exploratory factor analysis (EFA) and it should be further enhanced using item response theory in future. Future studies need to include samples from different populations in Pakistan to bring out a more generalized view and try to minimize the variances in sample as much as possible for better results.

The scale is constructed using the basic features of women empowerment at its core and is applicable in various settings to measure the attitude towards women empowerment. It will be a helpful tool to be used in various health, employment and educational settings. Moreover, this instrument can be applied for research purpose of measuring attitude as a predictor in combination with other variables such as domestic violence and harassment.

Empowering of women is one of the main agendas of 2019 of United Nations for Asian countries where women are not given equal rights, because of which suffer socially and economically from various problems along with issues regarding physical and mental health. By identifying the attitudes of general population, their causes for their attitudes can help in betterment of the women empowerment process.

This paper in discussion is an original work and has been performed with the purpose of assessing attitudes of males and females regarding women empowerment as the previous measures are either not psychometric valid or are in interview or survey form. The current developed scale is an attempt to develop an instrument that can be globally used.

This paper aims to provide an assessment of tourism promotion in tourist destinations and airports (TPTDs) and to organize and classify the literature on tourism promotion, with the aim of staging the importance of this topic and encouraging future research in the projection of tourism and marketing sectors.

The paper uses the Social Sciences Citation Index (SSCI) database to analyze the bibliometric in TPTDs topic from 2000 to 2021. Additionally, the paper also uses the visualization of similarities (VOS) viewer software to map graphically the bibliographic material. The graphical analysis uses bibliographic coupling, co-citation, citation and co-occurrence of keywords.

This study provides an amended new definition of tourism promotion, which is the efficient management of a destination’s resources and strategic plans by destination marketing organizations (DMOs) to adapt the tourism supply to market trends and will empower tourists to visit such destinations. Furthermore, results also show a new paradigm applied to TPTDs topic and classified in five first-order research streams. Digital and mobile marketing, infrastructure, branding, quality, accessibility and information factors about a specific destination which are mostly demanded by tourists are considered as an important means of promotion for the tourism industry.

The contribution of this study is important to identify new challenges and opportunities for researchers, DMOs, airport and airlines operators and stakeholders, as disentangling existing contradictions and applying new theoretical framework to make better future decisions by researchers and organizations to provide higher quality to new research in the context of the TPTDs.