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This study aims to evaluate and assess the elastoplastic properties of Ti-6Al-4V alloy manufactured by Arcam Q20 Plus electron beam melting (EBM) machine by a tensile test campaign and micro computerized tomography (microCT) imaging.

ASTM E8 tensile test specimens are designed and manufactured by EBM at an Arcam Q20 Plus machine. Surface quality is improved by machining to discard the effect of surface roughness. After surface machining, hot isostatic pressing (HIP) post-treatment is applied to half of the specimens to remove unsolicited internal defects. ASTM E8 tensile test campaign is carried out simultaneously with digital image correlation to acquire strain data for each sample. Finally, build direction and HIP post-treatment dependencies of elastoplastic properties are analyzed by F-test and t-test statistical analyses methods.

Modulus of elasticity presents isotropic behavior for each build direction according to F-test and t-test analysis. Yield and ultimate strengths vary according to build direction and post-treatment. Stiffness and strength properties are superior to conventional Ti-6Al-4V material; however, ductility turns out to be poor for aerospace structures compared to conventional Ti-6Al-4V alloy. In addition, micro CT images show that support structure leads to dense internal defects and pores at applied surfaces. However, HIP post-treatment diminishes those internal defects and pores thoroughly.

As a novel scientific contribution, this study investigates the effects of three orthogonal build directions on elastoplastic properties, while many studies focus on only two-build directions. Evaluation of Poisson’s ratio is the other originality of this study. Furthermore, another finding through micro CT imaging is that temporary support structures result in intense defects closer to applied surfaces; hence high-stress regions of structures should be avoided to use support structures.

The research was carried out to statistically evaluate the relationship between the safety measures at the construction sites and the actual and perceived knowledge levels of the employees about these measures.

Face-to-face surveys were conducted with the workers. The survey included some perception-based questions about preventive measures at the construction site, as well as determining the level of awareness of employees on occupational health and safety (OHS) practices. The data were analyzed with descriptive statistical methods and bivariate correlation analysis.

The actual knowledge levels of workers on OHS measures in the workplace is significantly lower than their perceived knowledge levels. However, there is a positive, linear and strong relationship between the actual knowledge levels of the employees about some OHS rules applied in the workplace and the general level of knowledge they perceive about themselves. Some protective measures such as occupational safety expert, OHS board, employee representatives, training and information activities at construction sites positively affect the safety awareness of employees. However, low-frequency and documentation-intensive activities such as risk assessment, emergency activities and periodic controls have no or weak correlations.

Perception-based opinions of construction site workers on occupational safety issues are transformed into numerical data and analyzed with a quantitative method.

The purpose of this paper is to evaluate the effect of post process combinations, e.g. hot isostatic pressing (HIP) only, HIP + T6 heat treatments, and T6 only, with different aging time, on surface properties, microstructure and mechanical properties of stress-relieved AlSi10Mg parts produced by direct laser metal sintering.

HIP process and HIP + T6 heat treatments were applied to as stress-relieved direct laser metal sintered (DMLS) AlSi10Mg parts. Aging times of 4 and 12 h are selected to examine the optimum duration. To analyze the advantages of HIP process, a T6 heat treatment with 4 h of aging was also applied. Densities, open porosities and roughness values of as stress-relieved, HIPed, HIP + T6, and T6-only samples were measured. The samples were characterized by OM and SEM together with EDX analysis. An image analysis study was made to evaluate the inner pore structure, thereby to understand the mechanical behavior.

HIP process does not cause a significant change in surface porosity; yet it has a positive influence on inner porosity. HIP process results in a microstructure of the aluminum matrix surrounded by a network of micron and nano size Si particles. Additional heat treatment results in larger particles and precipitation. After HIPing, ductility increases but strength decreases. Samples aged 4 h present improved yield and tensile strength but decreased elongation, yet samples aged for 12 h reach a combination of optimum strength and ductility. The lower level of tensile strength and ductility in T6-only condition indicates that HIP process plays a crucial role in elimination of the porosity thus improves the effectiveness of subsequent heat treatment.

The study investigates the effect of post-process conditions and optimizes the aging time of the T6 heat treatment after HIP process in order to obtain improved mechanical properties. The stress-relieved state was chosen as the reference to prevent distortion during HIPing or heat treatment.

The present paper aims to systematically investigate the influence of building orientations (0°, 15°, 30°, 45°, 60°, 75°) and heat treatment processes on the macro-/micro-structural, mechanical and electrochemical behaviors of selective laser melting (SLM) prepared AlSi10Mg alloy parts.

AlSi10Mg samples were produced by the SLM method using standard processing parameters at 0°, 15°, 30°, 45°, 60° and 75° building angles. The effects of building orientations on the physical, mechanical and electrochemical properties of the alloy were investigated.

With the increase in the building orientation from 15° to 75°, the structural defects were found reducing. The effect of step size of inclined geometries was found to significantly influence the mechanical and electrochemical properties of the AlSi10Mg samples. Tensile strength for samples fabricated at lower angles (0°, 15°, 30°) reported a drop of approximately 11% than SLM 0° samples. Moreover, the tensile strength was found to decrease from 412.35 ± 9.568 MPa for the as-built samples to 290.48 ± 12.658 MPa, whereas the fracture strain increases from 3.32 ± 0.56% to 5.6 ± 0.6% when the as-built sample was treated with T6 treatment. This study indicates that the microstructure and mechanical properties of SLM-processed AlSi10Mg alloy can be tailored by a suitable heat treatment or building angle.

Microstructural and mechanical behavior of horizontal or vertically built SLM components have already been demonstrated several times. However, the influence of different building orientations, such as 0°, 15°, 30°, 45°, 60°, 75°, has not been explored in-depth, particularly on corrosion and general mechanical performance. As a result, this work may be of significant relevance to academics and designers, given the varying orientation of internal component of SLM structures.

Departing from Turkish national debates around Islam, national belonging, and homosexuality during 2008–2011, this paper shows how “LGBT rights” discourses ultimately worked to position Muslim headscarf activists as against LGBT activists by rendering complex positions that do not follow easy “for vs. against” LGBT rights political formulas as “homophobic.” In return, this foreclosed potential solidarities differently injured citizens could have formed against increasing neoliberal state violence. I show that the multitude of Muslim women’s positions on the issue of LGBT rights complicates easy religious/secular binaries and illuminates how it is not only human rights discourses but also their “Western” critiques that travel transnationally. This story also contributes to current debates on postsecularism by illustrating how the same national context can house both liberal rights frameworks that can be used against pious Muslim subjects, and a monopolization of a definition of Islam for state power. Finally, I offer “politics of cruelty” and “right to sin” as alternative frameworks for imagining social justice outside of liberal rights-based politics.

This paper aims to investigate the effects of various heat treatments on microstructure, hardness, porosity and corrosion properties of the parts.

Hot isostatic pressing (HIP) process, various heat treatments and their combinations were applied to the AlSi10Mg parts produced by direct laser metal sintering (DMLS).

It has been found that the HIP process, which is a post-processing process, reduces the amount of porosity in DMLS-AlSi10Mg material, thus improves corrosion resistance significantly.

In this study, the HIP process and subsequent T6 heat treatments were applied to AlSi10Mg parts produced by the DMLS technique. The study aims to increase the corrosion resistance of AlSi10Mg parts by reducing porosity with the HIP process and by altering the microstructure with the T6 process.

Aritificial intelligence (AI)-focused enterprises purpose to provide value-creating and differentiated products and services using innovative technologies. For this reason, it is aimed to examine the effects of value creation, intellectual property and organizational creativity variables to make evaluations to increase the success of such enterprises.

Random sampling method was used in the research. The population of the research consists of AI-oriented enterprises in technoparks. On the specified days, short-term visits and surveys were conducted face-to-face. Name and similar personal information was not taken in the research and participation was made on a voluntary basis. A sample size of 500 units is a sufficient size at the 0.05 significance level. SmartPLS (4.0.8.4) licensed software was used in the research.

As a result of the collected data, it has been supported by hypotheses that value creation, intellectual property and organizational creativity have positive effects so that artificial intelligence-oriented enterprises can be successful in performance criteria.

Since the research was conducted by collecting data from artificial intelligence-oriented enterprises in technoparks in Istanbul, it would not be correct to evaluate the analysis results by making generalizations. For this reason, it is recommended that similar studies planned to be conducted in the future should contribute to the literature by developing the research model, taking into account the limited situation in the sample.

According to the results of the analysis of the effects of value creation, intellectual property and organizational creativity in artificial intelligence-oriented enterprises, in order to increase the success of such enterprises, they should offer more value to their customers, protect their technologies and increase their innovation capacity.

Value creation, intellectual property, and organizational creativity in AI-focused enterprises are important topics in a rapidly growing industry such as AI-focused enterprises. Therefore, a research investigating these variables together offers a different perspective than previous studies.

The purpose of this study is to investigate the factors which might affect the intention to use interactive whiteboards (IWBs) by university students, using Technology Acceptance Model by the structural equation modeling approach. The following hypothesis guided the current study: H1. There is a positive relationship between IWB self-efficacy and perceived learning (PL). H2. There is a positive relationship between IWB self-efficacy and perceived ease of use (PEOU). H3. There is a positive relationship between IWB self-efficacy and perceived usefulness (PU). H4. There is a positive relationship between PL and PEOU. H5. There is a positive relationship between PL and PU. H6. There is a positive relationship between PEOU and attitude. H7. There is a positive relationship between PU and attitude.

A survey method was used to collect the data. Purposive sampling was used, and 416 high-school students participated in the current study. Descriptive statistics and structural equation model conducted to test the proposed model were used in data analysis.

All hypotheses formulated within the scope of the research model were statistically confirmed. H1, which assumed that interactive whiteboard self-efficacy (IWBSE) have had a positive impact on PL, was found to be statistically significant. The impact of IWBSE on PL was 0.61 which means that if IWBSE increases one unit, the impact on PL will be an average of 0.61 points. The relationship between IWBSE, which is expressed in H2 and H3, and, respectively, PEOU and PU latent variables, was statistically significant. IWBSE mostly affected PEOU (= 0.51, t = 7.92), and then PU (= 0.16, t = 2.43). The relationship between PL – which is expressed in H4 and H5– and, respectively, PEOU and PU latent variables, was statistically significant. IWBSE mostly affected PU (= 0.63, t = 7.94), and then PEOU (= 0.27, t = 3.95).

It is aimed to transform the entire classes into computerized classes (Smart Class) around Turkey with FATIH project which includes usage of interactive boards. Because it is a very big project funded by the government, it is important to evaluate its adaptation among teachers and students. Therefore, the current study aims to investigate the factors which might affect the attitude to use IWBs by high-school students.

Industry 4.0 and the new technological transformation process it represents pose major challenges for the world today. Now, a new period has been entered, which will affect every point of daily life, from production to trade, and from health to entertainment. In terms of its scope and complexity, this period is unlike any that humanity has experienced before. The concept of Industry 4.0 is an external reflection of the innovations and applications made and to be made not only in today but also in the production methods of the future. Because this change and development occurs as a result of a certain accumulation and continues to occur continuously, it is evident that strategy is of great importance in today’s constantly changing and developing world. It is of great importance for leaders to develop strategies for evaluating the opportunity areas emerging by anticipating change in the Industry 4.0 process and to carry organizations and society into the future. Strategic leaders can do this effectively. At this point, strategic leadership is an important issue. Based on this idea, in this study, the strategic leadership issue from Industry 4.0 perspective will be examined in a theoretical context.