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The purpose of this paper is to enhance trust in e-commerce multi-agent systems by presenting a model, called RUU, to select the most trustworthy provider agent based on learning from previous interactions and computing reliability, unreliability and uncertainty.

The methodology comprises analyzing the most representative existing trust models, while a new concept was proposed and measured as unreliability. To make decision about the agents, RUU integrated reliability, unreliability and uncertainty components and used the TOPSIS multi-criteria decision method to select the most trustworthy provider agent. To evaluate the RUU model, the experimentation was carried out in two stages. First, the average accuracy of the model was investigated by simulating RUU in a multi-agent environment. Second, the performance of the model was compared with other related trust models.

The experimental results revealed that RUU model outperforms current models in providing accurate credibility measurements and computing an accurate trust mechanism for agents, also presenting a decision-making process to choose the most trustworthy provider agent.

The model presented based on different mathematical computations that take time to be calculated, which is a big limitation of computational models.

RUU enables an agent to make effective and sound decisions in light of the uncertainty that exists in e-commerce multi-agent environments.

This paper is beneficial to enhance the fulfilment of purchasing between provider and requester agents. In fact, the proposed model can ensure critical transactions performed securely in e-commerce multi-agent environments.

Purpose: Investors and portfolio managers can earn profitably when they correctly predict when stock prices will go up or down. For this reason, it is crucial to know the effect levels of the factors that affect stock prices. In addition to macroeconomic factors, the psychological behavior of investors also affects stock prices. Therefore, the study aims to reveal the different sensitivity levels of the stock index against macroeconomic and psychological factors.

Design/Methodology/Approach: In this study, dollar rate (USD), euro rate (EURO), time deposit interest rate (IR), gold price (GOLD), industrial production index (IPI), and consumer price index (CPI) (inflation (INF)) were used as macroeconomic factors, while Consumer Confidence Index (CCI) and VIX Fear Index (VIX) were used as psychological factors. In addition, the BIST-100 index, which is listed in Borsa Istanbul, was used as the stock index. The sensitivity of the stock index to macroeconomic and psychological factors was investigated using the Multivariate Adaptive Regression Spline (MARS) method using data from January 2012 to October 2020.

Findings: In the analyses performed using the MARS method, the coefficients of INF, USD, EURO, IR, CCI, and VIX Index were found to be statistically significant and effective on the stock index. Among these variables, INF has the highest effect on stocks. It is followed by USD, IR, EURO, CCI, and VIX. GOLD and IPI variables did not show statistical significance in the model. The most important difference of the MARS model from other regressions is that each factor’s effect on the stock index is analyzed by separating it according to the value of the factor. According to the results obtained from the MARS model: (1) it has been determined that USD, EURO, IR, and CPI have both positive and negative effects on the stock market index and (2) CCI and VIX have been found to have negative effects on stocks. These results provide essential information about how investors who plan to invest in the stock index should take into consideration different macroeconomic and psychological values.

Originality/value: This study contributes to the literature as it is one of the first studies to examine the effects of factors affecting the stock index by decomposing it according to the values it takes. Also, this study provides additional information by listing the factors affecting the stock index in order of importance. These results will help investors, portfolio managers, company executives, and policy-makers understand the stock markets.

The aim of the research is to investigate wear performance of some phenolic composites with boric acid.

The brake lining which has new formulation has been produced by using various additive materials. Various techniques have been used in the production of brake lining. These phenolic composites were subjected to friction and wear tests under different loads, and changes in the hardness and microstructures were examined.

As a result of this study, the following findings are reported. It was not found a direct proportionality between hardness and wear resistance due to the complexity of composite structure. Heat treatment application changed the microstructure of the brake lining, and increased the hardness and also decreased the density. With the increasing of temperature, the ingredients in the braking pad were affected other due to faster diffusion. On the other hand, hardness of specimen increases due to heat treatment and also specific wear ratio changes. As a filling material, barite was used due to better performance in the environmental conditions. More wear was observed in the bigger powder particles comparing to the smaller ones due to more structural loss. Squealing was heard in fiber un‐reinforced brake lining due to more barite content. In the present samples, boric acid deports the water and establishing the structural equilibrium. Therefore, these samples supplied higher and stable friction of coefficient. Also, heat treatment supplied a stable friction coefficient. With the increasing of copper powder into specimens, friction coefficient also increased. Heat treatment made the increment of hardness of specimens and also it made effect on the hardness with strengthening bonds of interparticles.

Limitations in the present research are as follows: two different pressures and eight different temperatures were used and brake linings were subjected to wear test, hardness tests, microstructures were examined.

For future work, instead of buying expensive brake lining, new and cheaper phenolic linings are produced. By this process, economic benefit can be gained and also environmental protection can be succeeded in producing such asbestos free brake linings.

This paper fulfills an identified information and offers practical help to the industrial firms working with brake lining and also to the academicians working on wear of materials.

The purpose of this study was to investigate the use of boric acid as a friction modifier material in brake friction composites and to determine the effect of heat treatment applied during production on braking performance.

The addition of five different amounts of boric acid was balanced with cashew, which is in the friction modifier material group. The samples were produced in the following order: dry mixing, preforming and hot-pressing. The effect of the heat treatment that can be applied after the hot-pressing process on the braking performance was investigated. The tribological and physical properties of the samples were determined using tests performed according to appropriate standards. The microstructures of the friction surfaces were investigated using scanning electron microscopy.

It was observed that the tribological properties of brake friction composites containing 20% by weight of boric acid were improved. It has also been observed that the heat treatment applied after hot pressing increased the friction coefficient of the samples by 7% on average and decreased the specific wear ratio of the samples. When the surface morphologies of the samples are examined, it is seen that the friction layers of the heat-treated samples are wider, and the microvoids and cracks are reduced.

This study showed that boric acid can be used as a friction modifier in brake friction composites. It also revealed the tribological and physical contribution of the applied heat treatment to the composite. Thus, it guides brake friction composite manufacturers in the industry and researchers working in this field.

The purpose of this study is to evaluate the level of sustainability consciousness (SC) and sustainable development (SD) awareness of medical students, as well as to identify the factors associated with them.

This cross-sectional and descriptive study was conducted among 1,435 medical students. The socio-demographic questionnaire and the sustainability consciousness questionnaire (SCQ-L) were the data collection instruments.

A significant proportion of medical students had not heard of the concept of SD (63.6%), only 7.9% of the participants reported that they could define the SD concept. Female gender and good economic status were associated with significantly higher median SCQ-L total score (p = 0.001). Although all SD goals are closely related to health, almost half of the medical students reported no impact on SD. Besides, 47.8% of the medical students reported that physicians could have an active role in achieving SD.

As the realization of SD and health services are closely linked, it is important to examine the sustainability knowledge, attitude and behavior of health professionals.

This study examined the SD awareness and SC knowledge, attitude and behavior among medical students, the leading health-care professionals of the future.

Drawing on current development practice and literature on Entrepreneurial support organizations (ESO), such as accelerators, incubators, and labs, this chapter explores how refugees in Uganda are supported through entrepreneurial approaches. Following an exploratory method, interviews were conducted with proprietors and managers of ESO in Kampala, the capital city of Uganda. The findings show that while the majority of these organizations purport to follow an innovation discourse, in reality, they support refugees through a mixture of inclusion, resilience, and innovation-led approaches. Inclusion-led approaches focus on basic language skills, establishing peer relationships, and access to survival essentials. Resilience-led approaches nurture livelihood skills, building community ties, and access to seed-corn grants. Innovation-led approaches develop entrepreneurial skills, establishing extra-local connectivity and access to micro-finance. This chapter highlights the critical importance of inclusion and resilience-led approaches in developing supportive ESO for refugees.

The purpose of this paper is to investigate use of calabrian pine (pinus brutia) cone (CPC) dust along with borax (BX) to assess the effect of friction coefficient. Despite the number of research studies completed on the mechanism of friction in automotive brake lining materials, the phenomenon is still not fully understood. Complex mechano-chemical processes occurring on the friction interface of a composite friction material make it difficult to understand the correlation between the formulation of brake lining and the frictional performance.

In this study, the use of CPC dust along with BX has been investigated for assessing the effect on friction coefficient. CPC has resin in it. BX is a boron production which is widely used in boron glass production and in ceramic industry for increasing the heat- resistant and -forming abrasion resistant. Newly formulated brake lining material with five different ingredients has been tested under Friction Assessment and Screening Test. Friction coefficient, wear rate and scanning electron microscope for friction surface were examined to assess the performance of these samples.

Analysis of the experimental results shows that the brake lining material containing CPC and BX significantly improved the stability of the friction coefficient, fade and wear resistance.

Several investigations have been conducted to use different materials in brake pads. The brake pad standards have been provided in previous studies, as well as the aims for economical and sustainable production. In the present study, production of brake pads by CPC dust and BX has been executed. Parallel results have been presented between previously reported and present study, in view of brake characteristics and wear resistance. Use of the lower cost and productive organic sources of material are the main improvement of the present study.

Postpandemic efforts to rebuild have steered the global economy toward a more sustainable trajectory. It is imperative to acknowledge the pressing need for further enhancements in the sustainable development of the tourism industry. This study aims to examine the influence of personal factors, including environmental concern, cultural interest, travel lifestyle and involvement, on tourist satisfaction and revisit intention, using the theory of planned behavior (TPB) as its framework.

The data was gathered through surveys conducted in three of Türkiye’s most famous slow travel destinations: Seferihisar, Gökçeada and Akyaka. The analysis was carried out using SPSS and SmartPLS software, with subsequent structural model testing.

This study presents an extended model that incorporates four individual factors, tourist satisfaction, TPB and revisit intention. All hypotheses have been rigorously tested, and the model accounts for 60.4% of the variance in revisit intention. The findings are comprehensively discussed in this article, supported by relevant theoretical frameworks.

Future research avenues could delve into the evolution of slow tourism in both developed and developing countries, assess disparities in revisit intentions between slow tourism and mass tourism destinations and investigate the prospects of sustainable tourism development in the postpandemic era.

The authors use the TPB to examine individual factors, tourist satisfaction and revisit intentions, aiming to build an extended model to gain a deeper understanding of the slow tourist decision-making process.