Juan Esteban Aponte Gonzalez, William Jordan Wright, Raden Gustinvil and Emrah Celik
Direct ink writing (DIW) is a robust additive manufacturing technology for the fabrication of fiber-reinforced thermoset composites. However, this technique is currently limited…
Abstract
Purpose
Direct ink writing (DIW) is a robust additive manufacturing technology for the fabrication of fiber-reinforced thermoset composites. However, this technique is currently limited to low design complexity and minimal heights. This study aims to investigate the feasibility of UV-assisted DIW of composites to enhance the green-part strength of the printed inks and resolve the complexity and the height limitations of DIW technology.
Design/methodology/approach
The experimental approach involved the preparation of the thermoset inks that are composed of nanoclay, epoxy, photopolymer and glass fiber reinforcement. Composite specimens were fabricated in complex geometries from these ink feedstocks using UV-assisted, hybrid 3D-printing technology. Fabricated specimens were characterized using optical microscopy, three-point bending mechanical tests and numerical simulations.
Findings
The introduced hybrid, UV-assisted 3D-printing technology allowed the fabrication of tall and overhanging thermoset composite structures up to 30% glass fiber reinforcement without sagging during or after printing. Glass fiber reinforcement tremendously enhanced the mechanical performance of the composites. UV-curable resin addition led to a reduction in strength (approximately 15%) compared to composites fabricated without UV resin. However, this reduction can be eliminated by increasing the glass fiber content within the hybrid thermoset composite. Numerical simulations indicate that the fiber orientation significantly affects the mechanical performance of the printed composites.
Originality/value
This study showed that the fabrication of high-performing thermoset composites in complex geometries was possible via hybrid DIW technology. This new technology will tremendously expand the application envelope of the additively manufactured thermoset composites and the fabrication of large composite structures with high mechanical performance and dimensional freedom will benefit various engineering fields including the fields of aerospace, automotive and marine engineering.
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Tugrul Oktay, Harun Celik and Ilke Turkmen
The purpose of this paper is to examine the success of constrained control on reducing motion blur which occurs as a result of helicopter vibration.
Abstract
Purpose
The purpose of this paper is to examine the success of constrained control on reducing motion blur which occurs as a result of helicopter vibration.
Design/methodology/approach
Constrained controllers are designed to reduce the motion blur on images taken by helicopter. Helicopter vibrations under tight and soft constrained controllers are modeled and added to images to show the performance of controllers on reducing blur.
Findings
The blur caused by vibration can be reduced via constrained control of helicopter.
Research limitations/implications
The motion of camera is modeled and assumed same as the motion of helicopter. In model of exposing image, image noise is neglected, and blur is considered as the only distorting effect on image.
Practical implications
Tighter constrained controllers can be implemented to take higher quality images by helicopters.
Social implications
Recently, aerial vehicles are widely used for aerial photography. Images taken by helicopters mostly suffer from motion blur. Reducing motion blur can provide users to take higher quality images by helicopters.
Originality/value
Helicopter control is performed to reduce motion blur on image for the first time. A control-oriented and physic-based model of helicopter is benefited. Helicopter vibration which causes motion blur is modeled as blur kernel to see the effect of helicopter vibration on taken images. Tight and soft constrained controllers are designed and compared to denote their performance in reducing motion blur. It is proved that images taken by helicopter can be prevented from motion blur by controlling helicopter tightly.
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Onur Çomakli, Mustafa Yazici, Tuba Yetim, Fatih Yetim and Ayhan Celik
This paper aims to investigate the structural, tribological and electrochemical properties of Ag2O, ZnO, NiO coatings and Ag2O/ZnO/NiO nanocomposite films deposited on…
Abstract
Purpose
This paper aims to investigate the structural, tribological and electrochemical properties of Ag2O, ZnO, NiO coatings and Ag2O/ZnO/NiO nanocomposite films deposited on commercially pure titanium.
Design/methodology/approach
Ceramic thin films (Ag2O, ZnO, NiO coatings and Ag2O/ZnO/NiO nanocomposite film) were deposited on commercially pure titanium (CP-Ti) substrate. Surface characterization of the uncoated and coated samples was made by structural surveys (scanning electron microscopic examinations and X-ray diffraction analyses), hardness measurements, tribological and corrosion experiments.
Findings
Results were indicated that sol-gel coatings improved the wear and corrosion resistance of CP-Ti, and the best results were seen at the nanocomposite coating. It may be attributed to its small grain size, high surface hardness and high film thickness.
Originality/value
This study can be a practical reference and offers insight into the influence of nanocomposite ceramic films on the increase of hardness, tribological and corrosion performance. Also, the paper displayed a promising approach to produce Ag2O/ZnO/NiO nanocomposite coating on commercially pure titanium implants for biomedical applications.
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The aim is to provide detailed mechanical and metallurgical examinations of ion‐nitrided austenitic‐stainless steels.
Abstract
Purpose
The aim is to provide detailed mechanical and metallurgical examinations of ion‐nitrided austenitic‐stainless steels.
Design/methodology/approach
Austenitic‐stainless steel was the material chosen for the present study. Ion nitriding process was applied to fatigue and tensile samples prepared by machining. Process temperature was 550°C and treatment time period 24 and 60 h. Then, tensile, fatigue, notch‐impact, hardness tests were applied and metallographic examinations were performed.
Findings
High temperature and longer treatment by ion nitriding decreased fatigue and tensile strengths together with notch‐impact toughness. Scanning electron microscopy and energy dispersive X‐ray spectroscopy analysis revealed formation of nitrides on the sample surfaces. Surface hardness increased with an increase in process time due to diffusion of nitrogen during ion nitriding.
Research limitations/implications
It would be interesting to search the different temperature and time intervals of the ion nitriding. It could be a good idea if future work could be concentrated on ion nitriding on welded stainless steels.
Practical implications
Surfaces of mechanical parts are exposed to higher stress and abrasive forces compared to inside mechanical parts during the time period that mechanical components carry out their expected functions. When stresses and forces exceed the surface strength limit of the material, cracks begin to form at the material surface leading to abrasion and corrosion. Therefore, surface strength of materials needs to be increased to provide a longer service life. Ion (plasma) nitriding is a possible remedy for surface wear.
Originality/value
The main value of this paper is to contribute and fulfil the detailed mechanical and metallurgical examinations of ion‐nitrided austenitic‐stainless steels that are being studied so far in the literature.
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Narayanage Jayantha Dewasiri, Angodage Kalpani Madhushika Pigera, Karunarathnage Sajith Senaka Nuwansiri Karunarathne and Mananage Shanika Hansini Rathnasiri
This study examines the impact of financial services employees’ engagement on the attitude toward artificial intelligence (AI) in Sri Lanka. The model developed in this study…
Abstract
This study examines the impact of financial services employees’ engagement on the attitude toward artificial intelligence (AI) in Sri Lanka. The model developed in this study comprises three constructs to demonstrate employee engagement (EE), namely, psychological state engagement (PSE), trait engagement (TE), and cognitive engagement (CE). Further, the model tests the moderating effect of age and gender on the relationship between EE and attitude toward AI. The authors conducted this research through a survey of 200 employees at Sri Lankan financial service firms. The findings indicate that EE substantially impacts attitudes regarding AI. Additionally, PSE, CE, and attribute engagement substantially affect how people feel about AI. Further, age has a moderating effect on the association between EE and attitude toward AI among financial services personnel. Based on the findings and discussion, the researcher recommends AI’s most significant importance in promoting a high level of engagement. The results would be helpful for both academic researchers and practitioners, especially HR managers, to understand the status of AI in Sri Lanka and formulate strategies to expedite EE.
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Mehmet Bağış, Mehmet Nurullah Kurutkan and Liridon Kryeziu
This research aims to determine the contribution of publications in the context of Türkiye to the international entrepreneurship literature between 2005 and 2022. We examined 471…
Abstract
This research aims to determine the contribution of publications in the context of Türkiye to the international entrepreneurship literature between 2005 and 2022. We examined 471 articles published in international journals in the Web of Science (WoS) Core Collection database using bibliometric analysis techniques. We analyzed the data with the software Biblioshiny+Bibliometrix, SciMAT, and VOSViewer. We used performance, theme and evolution, co-authorship, and document analysis in data analysis. Performance analysis findings show that the most publications were made in 2021, the journal with the most publications was sustainability, and the author with the most publications was Bakır, C. Theme and evolution analysis revealed that the motor themes were corporate entrepreneurship, gender and entrepreneurial intentions in the first period (2005–2014), while institutional entrepreneurship stood out as the niche theme. In the second period (2015–2022), “corporate entrepreneurship” and “performance” emerged as the motor themes, while the niche themes in this period were “Syrian refugees” and “entrepreneurial intentions.” Document analysis findings show that the most studied entrepreneurship types are gender, family, corporate, social, and small business, respectively. In addition, immigrant/refugee entrepreneurship is emerging as a new topic, while indigenous entrepreneurship, informal entrepreneurship, sustainable entrepreneurship, and religion entrepreneurship are the most minor studied topics in entrepreneurship. Evidence-based decision-making inputs were obtained for those holding the resource allocation authority in Türkiye. Policymakers and funders, as well as individuals and institutions that want to design the future in terms of resources, can benefit from the findings and analysis of this chapter. Türkiye, which ranks 26th in the world regarding entrepreneurship, must develop a policy based on data.
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This study includes process planning of prismatic parts by means of an expert system. On the computer controlled machine tools, operation methods and mostly used process types in…
Abstract
This study includes process planning of prismatic parts by means of an expert system. On the computer controlled machine tools, operation methods and mostly used process types in manufacture are drawn with solid modelling. Feature recognition process is achieved with the “B‐Rreb” modelling method to give vectorel direction knowledge and adjacent relationships of surface using the STEP standard interface program. Furthermore, operation type and sequence of operation are defined for the prismatic parts by using the databases achieved from the feature recognition module. This developed method was prepared on an IBM compatible PC by using C++ programming language for this purpose and is explained with a sample.
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Yasar Totik, Akgun Alsaran, Ayhan Celik and Ihsan Efeoglu
This work aims to investigate the wear behavior of manganese phosphate coating on plasma nitrided AISI 5140 steel.
Abstract
Purpose
This work aims to investigate the wear behavior of manganese phosphate coating on plasma nitrided AISI 5140 steel.
Design/methodology/approach
Prior to manganese phosphate coating, plasma nitriding of substrates was performed at gas mixture of 50 percent H2 and 50 percent N2, for the different treatment parameters. The structural, mechanical and tribological properties of the substrates were determined using hardness test, optical microscope, scanning electron microscopy , X‐ray diffraction and pin‐on‐disk tribotester. The wear behavior of untreated, nitrided and duplex treated substrates was evaluated under dry sliding conditions.
Findings
The results indicated that the duplex treatment improved the wear behavior. It was also observed that manganese phosphating of the nitrided substrates at low temperature (450°C‐2h‐N) resulted in a decrease of the wear rate and yielded a reduction in the friction coefficient by forming a transfer film at the counter face.
Originality/value
This study can be a practical reference and offers insight into the effects of duplex treating on the increase of wear resistance.
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Bikash Barua, MM Obaidul Islam, Habiba Kibria and Rupam Barua
Creativity is widely recognized as a key driver of innovation and competitive advantage in today’s dynamic business landscape. As organizations strive to foster a culture of…
Abstract
Purpose
Creativity is widely recognized as a key driver of innovation and competitive advantage in today’s dynamic business landscape. As organizations strive to foster a culture of innovation, it becomes imperative to understand the factors that enhance creativity among employees. This study aims to explore the role of employee empowerment in promoting creativity at the workplace.
Design/methodology/approach
This study used empowerment measures to determine the impact of employee empowerment on employee creativity. Creativity was also measured based on constructs reviewed in literature. An online questionnaire survey was conducted among 170 faculty members of different private universities of Bangladesh. The sample was chosen based on a convenience method. The responses were analyzed using partial least square (PLS) approach with the help of software SmartPLS.
Findings
This study comes to the conclusion that employee empowerment plays a crucial role as a forerunner to creativity at work. The configuration process is mostly accelerated and facilitated by university officials.
Research limitations/implications
Because they are statistically significant in establishing a climate for employee creativity at work, it is necessary to empirically determine the percentage impact level of the constructs of employee engagement known as “Leadership and Organizational Culture” and “Internal and External Enhancement Factors.” In addition, employee engagement is not the sole element influencing creativity at work. This suggests the need to quantify the relative influence that employee engagement has on other workplace drivers of creativity and innovation.
Practical implications
This study will help university authorities to instill management development programs to enhance their understanding about employees’ different psychological needs and expectations. Moreover, university management can find ways to implement various teacher development programs to promote growth mindset among the teachers. Organizations can leverage these insights to design and implement strategies that empower employees, leading to a more innovative and adaptable workforce.
Social implications
The implications of this research extend beyond individual organizations to society as a whole, as fostering creativity has broader implications for economic growth, productivity and overall well-being. By nurturing employee empowerment, organizations can not only enhance their competitive advantage but also contribute to societal progress through the generation of novel ideas, products and services.
Originality/value
This study was conducted on the private university faculty members to understand how the empowerment works in imparting creativity. The context of this study was educational institutions in contrast to the commercial organizations.
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This study aims to understand the potential influence of several factors that may affect females’ intentions to undergo breast cancer screening (BCS) in Jordan.
Abstract
Purpose
This study aims to understand the potential influence of several factors that may affect females’ intentions to undergo breast cancer screening (BCS) in Jordan.
Design/methodology/approach
A positivistic research methodology was used with the aim of gathering and interpreting the data quantitatively. A questionnaire was created and given to the selected respondents. Females who were at least 18 years old made up the study’s population. In addition, using a sample size of n = 237 was warranted and appropriate. Data were collected from Karak, Tafilah, Aqaba and Ma’an, four cities in southern Jordan. Smart partial least squares version 4.0.9.2 and SPSS version 26 have been used for data analysis.
Findings
The findings showed that attitudes, subjective norms, disease susceptibility and cues-to-action among females have a significant impact on their intention to undergo BCS. Whilst, the benefits of using BCS have not been shown to have a substantial impact on females’ intentions to undergo BCS. Furthermore, this study indicated that there were no significant differences between females’ intention to conduct BCS and the control variables (age and education).
Research limitations/implications
There are specific restrictions in place. First, although the study’s sample size of respondents was adequate, it would be advantageous to have a larger sample size in the future to improve the reliability of the results. Second, the BCS behavior in Jordan’s southern cities was the sole subject of this study. Therefore, it would be beneficial to also explore other areas of Jordan. Third, only female candidates for BCS were examined in this study. It might be necessary to do a more thorough investigation to find the obstacles preventing them from performing the test. Fourth, the current study did not analyze the actual behavior required to perform the BCS test; instead, it sought to understand females’ intentions for undergoing the test. Therefore, it would be beneficial to research actual female behavior toward BCS in the future. The current study also used a quantitative research methodology. Therefore, more study is required using qualitative techniques like focus groups, interviews and brainstorming to better understand females’ intentions toward BCS.
Originality/value
According to the author’s best knowledge, this study marks the first effort to highlight behavioral intentions toward performing BCS in the Jordanian context. In addition, by incorporating extra factors obtained from the health belief model within the context of BCS behavior, the current study broadens the theory of reasoned action. This can be viewed as a significant contribution to the subject’s theoretical foundations. Besides, the current study incorporated demographic characteristics and used them as a control variable. This can be seen as another contribution to the literature on health-care marketing in the case of BCS.