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The purpose of this study is to investigate the effects of air-suction slots geometry on the condensing zone of pneumatic compact spinning.

This paper investigated the condensing zone of pneumatic compact spinning with perforated drum for different structures of air-inlet slot geometry with computational fluid dynamics. For this purpose, three air-suction guides with different air-slots were designed. To create the condensing zone for the numerical simulation, a suction insert and the perforated drum were also designed. Flow velocity components on the X, Y, and Z axes, static pressure distribution and the streamline diagram were used for comparative analysis. Designed air-suction guides were produced with a 3D printer and used for yarn production.

Numerical simulation results showed that condensing effects were provided for all three types of air-suction guides and approaching air-slots on the suction guides resulted in greater flow components but may cause fluctuations. Experimental results also showed that actual flow velocity components (Z-axis) are effective on hairiness (H) properties of the yarn while assisting flow-velocity components are more effective on the evenness and tenacity properties of the yarn.

This paper presents the numerical flow field simulation of compact spinning for different structures of air-suction guides with detailed measurements. To know the effects of air-suction guides on the condensing zone may be helpful to improve yarn properties. In addition, a 3D printer was used for the production of designed parts.

The purpose of this study is to explore the effect of stitch type and stitch direction on the dynamic drape behavior of the woven fabric.

In this paper, the effectiveness of stitch type and stitch directions on dynamic drape behaviors were investigated. Fabric parts were sewn together with two types of the stitch (lockstitch and overlock stitch) on three different stitch directions (warp, weft and bias (45°)). The static drape coefficients (SDC) of unsewn and sewn fabrics were measured according to the image process method. Dynamic drape coefficients (DDC) of fabrics were also measured using the same method at six different (25, 50, 75, 100, 125, 150 rpms) rotation speeds. Additionally, bending length and bending rigidity were measured using the Cantilever test method.

Experimental results showed that stitch type and stitch directions are effective on the dynamic drape behaviors of the fabric. Overlock stitch resulted in greater DDC than the lock stitch. For both of the stitch type, DDC for the stitch on the warp direction are greater than the stitch on the weft and bias direction for all speeds. In addition, bending length, hence the bending rigidity, are greater for overlock stitch type and always weft direction resulted in greater than the warp and bias direction.

Fabric drape is vital for garment appearance and is gaining popularity with the advancement of virtual technology, enabling virtual visualization of garments. While previous studies have predominantly examined either the static or dynamic drape behavior of individual fabric panels, or solely focused on the static drape behavior of sewn fabrics, this study acknowledges the significance of incorporating the influence of stitch type and direction on dynamic drape behaviors. Considering that fabrics are sewn together to create garments and that DDC provides a more accurate representation of real-time fabric behavior compared to SDC, this research makes a valuable contribution to the existing literature by investigating the impact of stitch type and direction specifically on DDC.

The purpose of this study is to investigate surface treatments and fiber types on adhesion properties polylactic acid (PLA) three-dimensional (3D) parts printed on woven fabrics.

The cotton, flax and jute fabrics were exposed to alkali, hydrogen peroxide, stearic acid and ionic liquid treatments to modify surface characteristics before PLA 3D printing. The modification efficiency was assessed with Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) analyses. Then, fused deposition modeling (FDM) printer and PLA filament were used for 3D printing onto the untreated and treated fabrics. The adhesion strength between the fabrics and PLA 3D parts were tested according to DIN 53530 via universal tensile tester.

The fabric structure is effective on adhesion force and greater values were observed for plain weave fabrics. Maximum separation forces were obtained for alkali pretreated fabrics among jute and cotton. Hydrogen peroxide treatment also increased adhesion forces for jute and cotton fabrics while decreasing for flax fabrics. Stearic acid and ionic liquid treatments reduced adhesion forces compared to untreated fabrics. Treatments are effective to alter adhesion via changing surface chemistry, surface morphology and fabric physical properties but display different effects related to fabric material.

This study provides experimental information about effects of different fiber types and surface treatments on adhesion strength of PLA 3D parts. There is limited research about comprehensive observation on 3D printing on cellulosic-woven fabrics.

Beside the development of technology and accessibility, ease of use, ability to reach various products and compare many products at the same time make online shopping even more popular. Despite the great advantages provided by online shopping for either consumers or retailers, there are certain issues that must be solved to improve online shopping advantages. Finding right size is one of the biggest barriers against apparel online retailing. Since the use of apparels is directly related with fitting, choosing right size is becoming more critical for retailers and consumers. The purpose of this paper is to contribute to the solution of the problem.

For the study, the specific size measurements of male shirts (collar, shoulder, chest, waist, arm length in cm) from four different sizes (small, medium, large, x-large) and from eight different brands were collected and stored in a database. Totally, weight, height and body measurements (collar, shoulder, chest, waist and arm length in cm) of 80 male candidates, between the ages of 18 and 35, were measured individually. These data were then used for experiments.

Any product with known measurements can be compared with users’ body measurement based on fuzzy logic rule and the best-fitted size can be selected for users. Similarly, using the proposed web design, users are able to see desired products on users with similar body type.

In this study, a new mathematical method based on fuzzy relations for apparel size finder is proposed. Beside, this method can group users based on body measurements in order to find people with similar size.

The purpose of this paper is to analyse dynamic drape behaviours of 100% wool woven suiting fabrics considering real-time usage.

Dynamic drape coefficients of 100% wool woven fabrics were measured at different rotation speeds (25, 75, 125 and 175 rpm) with a commercially used fabric drape tester which works on image processing principle. Average daily walking speed of male and female volunteers was determined and the closest rotation speed was selected to calculate dynamic drape coefficient at walking (DDCw). Besides, bending rigidity and shear deformation properties, which are known to be related to the static drape behaviours of the fabrics, were also measured and the relationships between these parameters and DDCw were examined.

As a result of the experimental study, it was found that dynamic drape coefficients become greater, which means the fabrics take flatter position, with the increase of the rotation speed. In addition, it was also seen that parameters known to be related to static drape behaviours such as unit weight and bending stiffness have less effect on the dynamic drapes of fabrics. For the estimation of dynamic drape behaviour of fabrics, parameters such as static perimeter, dynamic perimeter, etc. are found more significant.

To date, although studies about dynamic drape behaviours of the fabrics claimed that dynamic drape gives more realistic results for in wearer experience, few of them focused on the rotation speed of dynamic drape tester for real-time usage. As dynamic drape behaviours of fabrics may differ for different rotation speed, determining appropriate speed in accordance with real-time usage gives more realistic results.

The purpose of this exhaustive experimental study is to investigate the fluid-structure interaction in the flexible membrane wings over a range of angles of attack for various Reynolds numbers.

In this paper, an experimental study on fluid-structure interaction of flexible membrane wings was presented at Reynolds numbers of 2.5 × 10⁴, 5 × 10⁴ and 7.5 × 10⁴. In the experimental studies, flow visualization, velocity and deformation measurements for flexible membrane wings were performed by the smoke-wire technique, multichannel constant temperature anemometer and digital image correlation system, respectively. All experimental results were combined and fluid-structure interaction was discussed.

In the flexible wings with the higher aspect ratio, higher vibration modes were noticed because the leading-edge separation was dominant at lower angles of attack. As both Reynolds number and the aspect ratio increased, the maximum membrane deformations increased and the vibrations became visible, secondary vibration modes were observed with growing the leading-edge vortices at moderate angles of attack. Moreover, in the graphs of the spectral analysis of the membrane displacement and the velocity; the dominant frequencies coincided because of the interaction of the flow over the wings and the membrane deformations.

Unlike available literature, obtained results were presented comparatively using the sketches of the smoke-wire photographs with deformation measurement or turbulence statistics from the velocity measurements. In this study, fluid-structure interaction and leading-edge vortices of membrane wings were investigated in detail with increasing both Reynolds number and the aspect ratio.

Because of competition, residential property developers use a variety of promotional tools to gain recognition and increase their market share and the demand for housing, and to manage their customer relations. This study aims to examine what real estate developers did to detect the need for types of housing, and pricing and promoting housing. It also sought clues about how they manage customer relations in residential sales.

In this study, semi-structured interviews were conducted with real estate developers. This study has heuristic characteristics based on qualitative data. Document reviews, descriptive analysis and discourse analysis were carried out on the interview data and other sources. As purposeful sampling is generally used in qualitative studies; intensity sampling, homogeneous sampling, criterion sampling and snowball sampling were used together in this study.

The study found that real estate developers were inadequate at advertising and promoting, allocated little budget for promotion and did not use technology sufficiently. The real estate developers gave discounts at rates that did not actually desire, had to create payment plans, and as a result, they lost customers because they could not manage customer relations well.

Interviews were conducted with 15 real estate developers who have been selling residential properties for more than 10 years in Süleymanpasa and Çorlu districts of Tekirdag. Data obtained are mostly qualitative.

This study aimed to determine real estate developers’ ability to implement a variety of promotional strategies and manage customer relations. Results and conclusions can offer significant clues about real estate developers with similar characteristics. Its conclusions of this study can be compared to similar studies of real estate developers in many regions of Turkey.

The purpose of this study is to review whether organization identification has a role of mediation and whether emotional intelligence (EI) has a role of moderating in the relationship between organizational justice perception (OJP) and organizational citizenship behavior (OCB).

In order to achieve the aim of the research, the data obtained from 388 employees of six shipyards in Yalova-Altinova Shipyards by survey technique were analyzed. To test the research hypotheses, SPSS (v22) PROCESS macro (v3.4) plugin developed by Hayes (2019) and Model 4 and Model 5 were used via the Bootstrap 5,000 sampling technique.

This study found that OJP impacts organizational identification (OI) and OCB. In addition, the research findings indicate that OI positively impacts OCB. This research reveals that OI played a mediating role in the relationship between OJP and OCB. However, the authors do not find support for the hypothesis that direct effect of OJP on OCB differs depending on the level of EI level.

The major limitation of this study is its sample that included only employees in shipyards. The results of this study will hopefully offer important insights into understanding and directing the human resources in shipyards conducting activities of construction, manufacturing, maintenance on the ships available at the center of maritime transportations.

This study draws attention to the causal relationships between the perception of OJP, OCB, OI and EI, which affect the organizational attitudes and behaviors of employees.

The lack of a reliable and valid measurement tool for coding achievement emerges as a major problem in Turkey. Therefore, the purpose of this study is to develop a Scratch-based coding achievement test.

Initially, an item pool with 31 items was created. The item pool was classified within the framework of Bayman and Mayer’s (1988) types of coding knowledge to support content validity of the test. Then the item pool was applied to 186 volunteer undergraduates at Hacettepe University during the spring semester of the 2017-2018 academic year. Subsequently, the item analysis was conducted for construct validity of the test.

In all, 13 items were discarded from the test, leaving a total of 18 items. Out of the 18-item version of the coding achievement test, 4, 5 and 9 items measured syntactic, conceptual and strategic knowledge, respectively, among the types of coding knowledge. Furthermore, average item discrimination index (0.531), average item difficulty index (0.541) and Cronbach Alpha reliability coefficient (0.801) of the test were calculated.

Scratch users, especially those who are taking introductory courses at Turkish universities, could benefit from a reliable and valid coding achievement test developed in this study.

This paper has theoretical and practical value, as it provides detailed developmental stages of a reliable and valid Scratch-based coding achievement test.

Along with accounting scandals in the past, academics, researchers, and legislators have focused on fraud. The purpose of this study is to examine postgraduate and doctoral studies, articles, and books about forensic accounting and fraud audit published between the years 2008 and 2018 in Turkey. For this purpose, a total of 96 studies have been examined and 35 of these are master’s theses, 10 of them are PhD theses, 45 of them are articles, and six of them are books. These studies were presented in tables as classified. The studies examined in our research are summarized as year they were published, the author, and the scope of the topic and in terms of results. The conclusions of this study can be summarized as follows: (a) the majority of thesis published about forensic accounting and fraud audit are in 2011 and following years. In addition, most of the theses are focused on forensic accounting review rather than fraud audit. (b) Results in the articles reviewed are in the same direction with theses. (c) There are very few books about fraud audit and forensic accounting. One of them is related to fraud audit, while the rest of them are related to forensic accounting and forensic accounting profession. We suggest extending the scope of the study and making to other countries.