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Although the adoption of 3D printing technology in many sectors such as medicine, aerospace, jewelry and the food industry is remarkable, the adoption of 3D printing technology by hobbyists remains unknown. The purpose of this paper is to map the attitude of individuals toward this new technology, define critical factors that have an impact on hobbyists’ behavior and, finally, explore the impact of 3D printing on social, economic and environmental changes, as 3D printing technology redesigns manufacturing, thereby impacting many sectors of day-to-day life.

A survey has been carried out on Greek hobbyists, and valuable conclusions have been drawn. Data were collected using a structured questionnaire survey performed on a sample of 344 Greek consumers in this sector. A questionnaire of 30 questions was distributed electronically.

This paper contributes to the determination of the percentage of individuals that know about 3D printing, the factors that have a significant contribution to adoption of the technology and, finally, identifies the profile of those that use 3D printing technology either in their work or for their hobby. Using a factor analysis, the authors classified users into five categories based on their attitudes towards 3D printing adoption: “innovators,” “informed,” “ecologists,” “engineers” and “re-users.”

The authors believe that understanding the predictors of 3D printing technology adoption for personal use and its benefits will overcome a pertained research gap and establish an empirical nucleus for further studies in relevant contexts. This type of research is necessary to expand the survey to other European countries.

3D printing is not new, but rather is an emerging technology. Individuals are willing to adopt this innovative technology. Based on the results of our survey, a desktop 3D printer will be necessary for every home and office in the near future.

The impact of 3D printing technology on rural life and its social implications are open questions. In this paper, by identifying the groups of hobbyists, the authors determine their particular characteristics and their perspectives on this new technology. All of what is discussed above is valuable for mapping the characteristics of those who adopt this technology.

This study is attempting to determine the behavior of individuals towards 3D printing technology, their awareness and how familiar they are with this new technological innovation.

The purpose of this paper is to examine the efficiency of the four largest Greek banking organizations for the period 2004–2014, including both a period of strong economic growth and a period of economic crisis and recession, which is still plaguing the Greek economy and more specifically the Greek banking sector.

The study incorporates the application of financial ratio analysis and the data envelopment analysis (DEA) in order to calculate the technical efficiency of Greek financial institutions. More specifically, a two-stage output-oriented DEA model is developed in order to estimate the global efficiency of banks. The banking function is considered as consisting of two stages in series, a service/operational efficiency and a profitability efficiency. In both output-oriented models, methods of constant returns to scale and variable returns to scale were applied.

The results show that in terms of operational efficiency, banks started from a low rate of return in 2004, which improved until 2008, which marked the peak of operational efficiency. By 2010, the operating efficiency varied with downward trend until 2012–2013. In terms of profitability efficiency, the image is clearer, since the impact the financial crisis had on bank’s profit efficiency led, by 2012, to a plunge in the average efficiency by 30–40 percent.

A multi-stage DEA process, input oriented, was used in order to estimate changes in the performance and efficiency of banking system. The period 2004–2014 has not been examined until recently and all previous studies used the output-oriented DEA model.

This paper aims to examine customer switching behaviour in Greek banking services. More specifically it aims to investigate predictors of churn behaviour as part of customer relationship management (CRM).

The enhancement of existing relationships is of pivotal importance to banks, since attracting new customers is known to be more expensive. The paper discusses survival analysis based on data collected from customers of a leading financial services company. It examines a number of variables, which represent characteristics of the customers and of the offered services and products. By using life tables, it estimates the contribution of each separate factor in customers' switching behaviour in different periods of time.

A hazard proportional model is built to determine the risk of churn behaviour, which is the end‐result of all the examined factors.

Bank's management team could use the findings of our study, in order to determine specific attributes in designing financial services and products, which would add in customers' satisfaction.

The approach and results have significant implications for enlarging the duration of the relationship among customer and bank.

In the situation of financial crisis, the performance of banking and financial institutions is considered to be important for a country's economy. The purpose of this paper is to develop an index, called the “Bank Ranking Index” (BRI), which classifies banks in a descending order.

This study proposes the BRI, which is based on a set of quantitative indicators representing, the financial market, the bank's financial identity and its infrastructure and classifies banks in a descending order. Cluster analysis is also used in order to compare the results of the above classification.

The index is implied in a representative sample of 16 Greek banks. The results indicate that through the proposed approach the banks can improve their efficiency and their overall performance in order to satisfy customers' needs in a more efficient way.

The paper seeks the proposed index as a benchmarking tool, which could be valuable to the bank's management team in order to plan and configure its strategy of development.

Based on banks' characteristics and on financial data the paper introduce a simple index, the BRI, based on which the paper assess the performance of a bank institution.

Credit risk assessment has gained importance in recent years due to global financial crisis and credit crunch. Financial institutions therefore seek the support of credit rating agencies to predict the ability of creditors to meet financial persuasions. The purpose of this paper is to construct neural network (NN) and fuzzy support vector machine (FSVM) classifiers to discriminate good creditors from bad ones and identify a best classifier for credit risk assessment.

This study uses artificial neural network, the most popular AI technique used in the field of financial applications for classification and prediction and the new machine learning classification algorithm, FSVM to differentiate good creditors from bad. As membership value on data points influence the classification problem, this paper presents the new FSVM model. The instances membership is computed using fuzzy c-means by evolving a new membership. The FSVM model is also tested on different kernels and compared and the classifier with highest classification accuracy for a kernel is identified.

The paper identifies a standard AI model by comparing the performances of the NN model and FSVM model for a credit risk data set. This work proves that that FSVM model performs better than back propagation-neural network.

The proposed model can be used by financial institutions to accurately assess the credit risk pattern of customers and make better decisions.

This paper has developed a new membership for data points and has proposed a new FCM-based FSVM model for more accurate predictions.

In more than 100 years of aviation, significant progress has been made in flight control systems. The aircrafts that have entered service for the past ten years tend towards power-by-wire flight control with electrical actuators. The purpose of this study is to analyse the effects of electrical actuation on power consumption, weight and fuel consumption on a commercial transport aircraft.

The Airbus A321-200 aircraft was chosen as a case study for analysing the effects of electrical actuation on the flight control actuation system (FCAS) architecture, and Pacelab SysArc software was used for design, modelling and analysis. As alternatives to the existing system, hybrid and all-electric models are built to a set of design guidelines with certain limitations.

Compared to the existing FCAS architecture model, 80 kg weight savings in the hybrid FCAS architecture model and 171 kg weight savings in the all-electric FCAS architecture model were observed. In terms of fuel consumption, it has been observed that there is 0.25% fuel savings in the hybrid FCAS architecture model, and 0.48% fuel savings in the all-electric FCAS architecture model compared to the existing FCAS architecture model at 3200 NM.

In line with the data obtained from this study, it is predicted that electrical actuation is more preferable in aircraft, considering its positive effects on weight and fuel consumption.

In this study, three different models were created: the existing FCAS architecture of a commercial transport aircraft, the hybrid FCAS architecture and the all-electric FCAS architecture. Hybrid and all-electric models are built according to a set of design guidelines, with certain limitations. Then, similar flight missions consisting of the same flight conditions are defined to analyse the effects of power consumption, weight, and fuel consumption comparatively.

The presented research is carried out in reaction to the soaring costs of fuel and tight control over environmental issues such as carbon dioxide emissions and noise. The purpose of this paper is to study the feasibility of applying the environmental-friendly energy source in an unmanned aerial vehicles (UAVs) propulsion system.

Currently, the majority of UAVs are still powered by conventional combustion engines. An electric propulsion system is most commonly found in civilian micro and mini UAVs. The UAV classification is reviewed in this study. This paper focuses mainly on application of electric propulsion systems in UAVs. Investigated hybrid energy systems consist of fuel cells, Li-ion batteries, super-capacitors and photovoltaic (PV) modules. Current applications of fuel cell systems in UAVs are also presented.

The conducted research shows that hybridization allows for better energy management and operation of every energy source onboard the UAV within its limits. The hybrid energy system design should be created to maximize system efficiency without compromising the performance of the aircraft.

The presented study highlights the reduction of the energy consumption, necessary to perform the mission and maximizing of the endurance with simultaneous decrease in emissions and noise level.

The conducted research studies the feasibility of implementing the environmental-friendly hybrid electric propulsion systems in UAVs that offers high efficiency, reliability, controllability, lack of thermal and noise signature, thus, providing quiet and clean drive with low vibration levels. This paper highlights the main challenges and current research on fuel cell in aviation and draws attention to fuel cell – electric system modeling, hybridization and energy management.

The purpose of this paper is to address the challenge for knowledge exchange between disciplines that study past urban landscapes, such as archaeologists, historians and historical geographers and disciplines that work on new urban landscapes such as architects and spatial planners. It presents the design, deployment and evaluation of a heritage instrument, the “digital cultural biography” (DCB), which aims to allow future-oriented disciplines to make more historical and heritage informed decisions.

The paper makes three contributions. First it presents a methodology to disseminate geographic information across disciplines by applying the biography of the landscape research strategy. Second it translates this methodology to a digital instrument, the DCB, which makes it possible to configure the historical and heritage features diachronically as well as spatially. And third it evaluates the added value of this instrument by organizing a design concourse and applying various evaluation methods. The Roman neighbourhood of Testaccio functions as the use case for this study.

The research shows a high potential to use digital tooling based on geospatial technologies to support the dialogue between future and past-oriented disciplines.

The paper discusses how the recently developed biography of the landscape method can be used as a tool for collaboration between heritage managers and spatial planners. Moreover, for the first time it applies and evaluates digital tools and geospatial technologies to support this approach.

Considering both the current opportunities of the Internet of things (IoT) and aviation, as well as the potential opportunities they may offer for the future, it is understood that they are among the important issues that need to be examined in the literature. This study aims to provide an idea by conducting bibliometric and visualization analyses of the current trends and development opportunities of IoT and aviation.

In this study, descriptive and bibliometric analyses within the framework of co-author, co-citation, bibliographic coupling, and keyword co-occurrence analysis were carried out for publications found to be published between 2007 and 2023 in the Web of Science (WoS) database related to IoT and aviation. VOSviewer (ver. 1.6.18) program and the Biblioshiny application were used to create bibliometric networks and provide visualization.

As a result of some descriptive and visualization analyses, the current trend of publications on IoT and aviation and future publication opportunities has been revealed. It has been understood that the subject of IoT and aviation is one of the subjects whose number of publications has increased in recent years and has not yet fully matured in terms of the number of publications and has the potential to make new publications.

In this study, bibliometric analysis of IoT and aviation, which could not be found examined before in the literature, and the creation of existing bibliometric networks by visualizing were carried out.