The purpose of this work is to present the model of a Parabolic Trough Solar Collector (PTC) using the Finite Element Method to predict the thermal behavior of the working fluid along the collector receiver tube. The thermal efficiency is estimated based on the governing equations involved in the heat transfer processes. To validate the model results, a thermal simulation of the fluid was performed using Solidworks software. The maximum error obtained from the comparison of the modeling with the simulation was 7.6% at a flow rate of 1 L/min. According to the results obtained from the statistical errors, the method can effectively predict the fluid temperature at high flow rates. The developed model can be useful as a design tool, in the optimization of the time spent in the simulations generated by the software and in the minimization of the manufacturing costs related to Parabolic Trough Solar Collectors.

The study examines the impact of COVID-19 on the economies of Gulf Corporation Council (GCC) member states. The event study methodology was used to analyze Cumulative Abnormal Return (CAR) of GCC member states’ stock indexes: Kuwait Stock Exchange Index (KSE), Dubai Financial Market Index (DFM), Saudi Arabia Tadawul Index (TASI), Qatar Exchange Index (QE), Bahrain All Share Index (BHB), Oman’s Muscat Stock Exchange Index (MSM), Abu Dhabi Stock Exchange Index (ADX) while the S&P GCC Composite Index was used as a reference. Data obtained from 28 July 2019 to 27 July 2020, and 1 March 2020, designated as the event day, abnormal returns (AR) and cumulative average abnormal returns (CAARs) were examined across various time intervals. The findings reveal significant market reactions to the pandemic, characterized by fluctuations in abnormal returns and CAARs. Statistically significant abnormal returns and CAARs during certain time periods underscore the dynamic nature of market responses to the COVID-19 event. These results provide valuable insights for policymakers and market participants seeking to understand and navigate the economic implications of the pandemic on GCC economies. The study recommends that other GCC states, particularly Oman, consider the policies undertaken by Qatar, UAE, and Saudi Arabia, to avoid a long economic crisis.

Nanotechnology is recognized as one of the high and new technologies in the 21st century. Carbon nanotubes have been widely used in molecular sieve, drug transport and seawater desalination due to their unique mechanical, electrical, optical and other excellent properties. As the main representative of carbon nanotube macroscopic materials, carbon nanotube film not only retains the microscopic properties of carbon nanotube, but also has good mechanical properties and stable chemical properties. The preparation and application of carbon nanotubes (CNTS) have attracted extensive attention from scholars at home and abroad. In this paper, the research on carbon nanotube films in recent years is reviewed. Based on the preparation of carbon nanotube films, chemical vapor deposition, LB (Langmuir-Blodgett) film and electrostatic layer-by-layer self-assembly techniques are briefly described. In addition, the applications of carbon nanotubes in biological field, photoelectric nano devices, water treatment, seawater desalination and other fields are also described.

Choosing a university is a crucial decision for each field of study, as it significantly influences the quality of graduates. An important factor in this decision is the university’s annual benchmark scores. The benchmark score represents the minimum score required for admission. This study evaluates the benchmark scores in the logistics sector for several prominent universities in Vietnam during the period 2021–2023. The research process utilized data on the benchmark scores for the years 2021, 2022, and 2023. The weights of these benchmark scores were calculated using the Rank Order Centroid (ROC) method, and the Probability method was employed to compare the benchmark scores of the universities. The analysis identified C3 as the criterion with the highest importance, while U3 emerged as the top-ranked alternative. The two-stage comprehensive sensitivity analysis revealed that universities consistently ranked high or low regardless of the method used to calculate benchmark score weights or the method employed for ranking. Additionally, the smallest weight change that affected the overall Probability ranking was 4.61%. This study provides significant guidance for students in selecting a university for logistics studies and serves as a foundational reference for universities to assess their capabilities in logistics education, thereby fostering healthy competition among institutions.

Illegal, unreported, and unregulated fishing (IUU fishing) crimes by rogue fisheries companies are rife in the sea waters of Riau Province. However, this issue is rarely reported by those provincial journalists in the online media where they work. In fact, in Riau, there are 163 online media companies and 600 competent journalists; 200 of them live in capture fisheries center areas. Apart from the journalist competency factor, the decision to make IUU fishing news can also be influenced by the fisheries company intervention that committed the crime. Besides, the policy role of media leaders—editors, editors-in-chief, and media owners—also determines journalists’ decisions to make those news stories. This research aims to analyze the influence of journalist competence and fishing company intervention on the decision to make IUU fishing news, as well as the role of media leader policy as mediators in these influences. This survey involved 100 competent journalists as respondents. Data collection was carried out through a questionnaire containing a number of closed statements measured on a 5-point Likert scale, which was distributed to respondents. The data were analyzed using the Structural Equation Modeling (SEM) method. The research results show that the fishing company intervention has a negative and significant influence on the decision to make IUU fishing news in Riau, while journalist competence does not. Additionally, media leader policy was found to play a significant role in mediating the influence of fisheries company intervention and journalist competence on the decision to make IUU fishing news. The leader policy could prevent journalists from making IUU fishing news if fisheries companies, who are responsible for those crimes, intervene and request it. Those actions of media leaders need to be questioned because they can hamper the media’s function as a means of disseminating information, educating the public, and implementing social control, especially those related to combating IUU fishing crimes.