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Sectional warping is the most widely used warp preparation process in weaving. Winding all warp sections with the same length and same tension is a key factor for a good quality warp preparation. It is required that winding thickness (increase in radius due to warp winding) remains the same within and between warp sections. The purpose of this paper is to investigate winding thickness variations within and between warp sections, which can lead to quality problems in woven fabrics.

A measurement system is developed and then an experimental investigation into winding thickness variations is carried out. Winding thickness is measured with respect to number of drum revolutions using a laser sensor with 20 microns resolution. The number of drum revolutions and drum angular position are measured by an incremental encoder. Both sensors are mounted on an industrial sectional warping machine. A real-time software written in C programming language collects and records the data for all sections of warp with respect to drum number of revolutions and then results are evaluated to determine winding thickness variations.

Results show that warp sheet thickness starts with a higher value and it decreases up to around 30 drum revolutions and then it remains constant or decreases very slightly which can be considered as insignificant from practical point of view. Warp sheet thickness (i.e. thickness of one warp layer) fluctuates within each section up to 10 percent CV with five drum revolutions average warp sheet thickness. There are also warp sheet thickness variations between warp sections up to 3 mm.

Considering the short of practical research results on winding thickness variations in the literature, results of this study will be an original contribution to understanding winding thickness variation level. Also, results presented in this paper can be used to develop control algorithms for thickness control in sectional warping machines.

Yarns of different types are unwound from bobbins in different processes like warping, weaving, doubling and re-winding. It is required that yarn tension remains constant during unwinding in all these processes. Otherwise, it ends with product quality and process efficiency problems. The purpose of this paper is to investigate experimentally the effect of balloon length on yarn tension change with respect to bobbin diameter during unwinding in an attempt to obtain a minimum yarn tension variation.

An experimental set up was built. Bobbin diameter was measured by a laser sensor and yarn tension was measured by a single yarn tension sensor. Both sensor outputs were interfaced to a PC via a DAQ cad. A software program was developed in C programming language to read and record the tension and bobbin diameter simultaneously. Experimental study was conducted with three different balloon lengths for both continuous filament and spun yarns of four different yarn numbers and five different unwinding speeds.

Results showed that yarn tension change with bobbin diameter was affected in different ways with balloon length depending on yarn number, unwinding speed and yarn type.

Available literature on the effect of balloon length on yarn tension bobbin diameter relation is limited and measurements were generally conducted for three different bobbin diameters. Yarn tension bobbin diameter relation is obtained in this research for at least eight different diameters and more for three different balloon lengths covering practical application ranges. The results obtained can be used in the design of tension control system for warping and winding machines as well as for setting these machines for optimum efficiency.

The purpose of this paper is to investigate warp and weft crimp distribution over the fabric width and how it is influenced by warp tension distribution over the warp width.

An experimental design in this research includes air jet loom, tension sensor, inductive sensor and personal computer.

It is found that warp crimp in the fabric on the loom is higher in the edge zones than the middle of the fabric and warp crimp in the middle is higher than warp crimp in edge zones of the grey fabric. Weft crimp in the edge zones is higher than in the middle of the grey fabric. The reason behind warp tension and warp and weft crimp variations over fabric width is that weft yarn slips towards inside fabric at selvedges and gets relaxed during beat up.

It is proved that reducing weft yarn slip and therefore weft yarn relaxation during beat up will reduce warp tension and warp and weft crimp variations and improve the uniformity of fabric properties over the fabric width.

While former literature has shown that people have a strong tendency to seek religious support during difficult times, knowledge gaps exist in how the mechanism of religiosity works to support employees’ mental status and performance. Therefore, based on self-categorization theory, this study aims to examine the effects of employees’ intrinsic and extrinsic religiosity on building their mental toughness and mindfulness and the further formation of employees’ political skills.

Data was collected from 404 full-time hotel employees working in 34 hotels in Turkey during the coronavirus (COVID-19) pandemic in spring 2020. Structural equation modeling was used to examine the proposed hypotheses.

Results of this study show that intrinsic religiosity improves employees’ mental toughness, while extrinsic religiosity enhances employee mindfulness. Additionally, both mental toughness and mindfulness help employees to develop political skill.

This study enriches knowledge to workplace religiosity literature and expands the research scope of religion-related research in hospitality and tourism literature. Future studies are recommended to consider religious heterogeneity and longitudinal design.

To foster employee mental well-being, hotel firms should create a religious-friendly workplace and develop religion-friendly policies. Opportunities should be created within hospitality organizations for employees to develop and use their political skills in needed work aspects.

The findings of this study contribute to valuable theoretical and practical implications. To the best of the knowledge, this study is one of the first attempts to study hotel employees’ religiosity during the COVID-19 pandemic.

The purpose of this paper is to explore top government hands-on megaproject management model applied to Istanbul’s new airport megaproject. The study aims to find an answer to this research question: “How is the organizational design and management of a megaproject that has been alive in a confrontational socio-political environment and whose national strategic importance is high?”

Organizational theory and critical theory perspectives are used in this study. Istanbul’s grand airport is chosen as the case study. Interview, focus group and document analysis methods are used together. The research yields data from qualitative resources. Verbal and written materials are organized into three major themes and 27 key subjects for content analysis.

A top level of organizational management can be attained in the state in order for the mega projects with high national strategic importance to survive without problems and with high performance. The top government-level organizational structure implemented at Istanbul’s new airport has reduced complexity, risk and uncertainty; increased performance and product quality; and strenghtened inter-organizational compatibility and communication within the megaproject organization. However, this structuring also increased centralization, reduced transparency and direct public participation in the decision-making process.

The megaproject is run in strict confidence and limited information is shared gradually in a controlled way with public by the megaproject organization. Therefore, a qualitative methodology is followed and the usage of quantitative data remained limited in the research.

The study presents an exemplary top government-level megaproject management model for countries experiencing strong socio-political conflicts and aiming to perform megaprojects with high national strategic importance.

The organization of Istanbul’s new airport megaproject offers an exemplary, flexible and innovative organizational management model for countries that want to realize mega projects with high national strategic importance and experience strong socio-political conflicts. The questions of how to cope with challenges, how to build management capabilities and how to improve the cooperation and coordination within megaprojects have found some answers with this study. In addition, this study provides an insight into how to make more effective objections to wrong megaproject practices and the right strategies that the opposing organizations can follow.

This empirical research widens and deepens the theoretical foundations of top government hands-on megaproject management. The study, which includes a process analysis, allows to better understand the philosophy, nature, success, planning process, social organization and dynamics of megaprojects and to explain them through the values and strategies of organizations.

For comfort evaluation of underwear pressure, this paper proposes an improved GA algorithm to optimize the weight and threshold of BP neural network, namely PSO-GA-BP neural network prediction model.

The objective parameters of underwear, body shape data, skin deformation and other data are selected for simulation experiments to predict the objective pressure and subjective evaluation in dynamic and static state. Compared with the prediction results of BP neural network prediction model, GA-BP neural network prediction model and PSO-BP neural network prediction model, the performance of each prediction model is verified.

The results show that the BP neural network model optimized by PSO-GA algorithm can accelerate the convergence speed of the neural network and improve the prediction accuracy of underwear pressure.

PSO-GA-BP model provides data support for underwear design, production and processing and has guiding significance for consumers to choose underwear.

Today’s organizations try to keep their employees loyalty but employees may still feel unsatisfied and adopt negative attitudes. Cynicism, as a negative attitude of employees toward their organization, leads to unwanted outputs such as lower performance or lower loyalties that can appear in every kind of sector. Accordingly, the purpose of this paper is to determine the effects of personality traits on organizational cynicism in the education sector.

This study used the survey method to collect data and survey forms were distributed to teachers from various private schools in Istanbul, Turkey. With the e-mail survey method, the authors received 254 healthy survey forms from teachers. For personality traits, the five-factor model of personality traits that was developed by McCrae and Costa (1987) was preferred and the organizational cynicism model was evaluated with three basic dimensions as based on Brandes’s (1997) model.

Based on data from 254 teachers of various private schools in Istanbul, interrelationships amongst personality traits and organizational cynicism were tested. On the basis of the partial least-squares method, the authors found that agreeableness had a negative effect on cognitive cynicism and affective cynicism, conscientiousness had a negative effect on cognitive cynicism and affective cynicism, neuroticism had a negative effect on cognitive cynicism and behavior cynicism, and openness to experience had a positive effect on cognitive cynicism and affective cynicism. Thus, it can be said that personality traits of teachers had a significant effect on organizational cynicism as a result of this study.

This study used two main scales: the scale of McCrae and Costa (1987) for personality traits and the scale of Brandes (1997) for organizational cynicism. The authors adapted both the scales for Turkish culture and the education sector that the results can be considered valid for only this study.

This study shows a significant effect of personality traits on cynicism in the education sector and thus can be considered to be useful for future studies.