Climate change is the most important environmental problem of the 21st century. Severe climate changes are caused by changes in the average temperature and rainfall can affect economic sectors. On the other hand, the impact of climate change on countries varies depending on their level of development. Therefore, the aim of this paper is to investigate the relationship between climate changes and economic sectors in developed and developing countries for the period 1990–2021. For this purpose, a novel approach based on wavelet analysis and SUR model has been used. In this case, first all variables are decomposed into different frequencies (short, medium and long terms) using wavelet decomposition and then a SUR model is applied for the examination of climate change effects on agriculture, industry and services sectors in developed and developing countries. The findings indicate that temperature and rainfall have a significant negative and positive relationship with the agriculture, industry and services sectors in developed and developing countries, respectively. But severity of the negative effects is greater in the agricultural and industrial sectors in all frequencies (short, medium and long terms) compared to service sector. Furthermore, the severity of the positive effects is greater in the agricultural sector in all frequencies of developing countries compared to the industrial and services sectors. Finally, developing countries are more vulnerable to climate change in all sectors compared to developed countries.
This study aims to elucidate the impact of marketing investment dimensions (MTS, MTOE, ROMI) on profitability indicators (ROA, ROE, GPM, OPM) and sustainable growth indicators (SGR, ARG) for service companies. The study population consisted of 135 service companies listed on the Amman Stock Exchange. A purposive sample of 55 companies was selected from this population. Financial reports and statements from 2018–2022 for these companies were analyzed to achieve the study objectives, employing appropriate statistical methods like multiple regression to test hypotheses. Previous literature shows conflicting results regarding the relationship between marketing investment dimensions and profitability/sustainable growth. Some studies found positive impacts, while others did not. This study contributes to this debate by providing statistical evidence. The results show that higher MTS, MTOE, and ROMI have a positive impact on SGR, OPM and ROA but a negative impact on GPM, ARG, and ROE. This underscores that marketing investments should be viewed in conjunction with overall operating expenses. Companies that control other expenses and increase the marketing investment proportion of total operating expenses may achieve better financial performance. Marketing investment metrics can serve as useful diagnostics and measures of effectiveness for improving marketing profitability, financial performance, and growth. In summary, this study statistically demonstrates the nuanced impacts of marketing investments on service company profitability and sustainable growth indicators. The results emphasize analyzing marketing spends in context of broader expenses and overall company financial health.
Beach protection is vital to reduce the damage to shorelines and coastal areas; one of the artificial protections that can be utilized is the tetrapod. However, much damage occurred when using a traditional tetrapod due to the lack of stability coefficient (KD). Therefore, this research aims to increase the stability coefficient by providing minor modifications to the cape of the tetrapod, such as round-caped or cube-caped. The modification seeks to hold the drag force from the wave and offer a good interlocking in between the tetrapod. This research applied physical model test research using a breakwater model made from the proposed innovative tetrapod with numerous variations in dimensions and layers simulated with several scenarios. The analysis was carried out by graphing the relationship between the parameters of the measurement results and the relationship between dimensionless parameters, such as wave steepness H/gT2, and other essential parameters, such as the KD stability number and the level of damage in %. The result shows that the modified and innovative tetrapod has a more excellent KD value than the conventional tetrapod. In addition, the innovative tetrapod with the cube-shaped has a recommended KD value greater than the round shape. This means that for the modified tetrapod structure and the same level of security, the required weight of the tetrapod with the cube cap will be lighter than the tetrapod with the round cap. These findings have significant practical implications for coastal protection and engineering, potentially leading to more efficient and cost-effective solutions.
Proposed herein is an environment-friendly method to realize oil/water separation. Nylon mesh is exposed to atmospheric pressure plasma for surface modification, by which micro/nano structures and oxygen-containing groups are created on nylon fibers. Consequently, the functionalized mesh possesses superhydrophilicity in air and thus superoleophobicity underwater. The water pre-wetted mesh is then used to separate oil/water mixtures with the separation efficiency above 97.5% for various oil/water mixtures. Results also demonstrate that the functionalized nylon mesh has excellent recyclability and durability in terms of oil/water separation. Additionally, polyurethane sponge slice and polyester fabric are also functionalized and employed to separate oil/water mixtures efficiently, demonstrating the wide suitability of this method. This simple, green and highly efficient method overcomes a nontrivial hurdle for environmentally-safe separation of oil/water mixtures, and offers insights into the design of advanced materials for practical oil/water separation.
In this paper, the characteristic behavior of the disc consisting of thermoplastic composite CF/PA6 material was considered. Analysis was made by taking into account the usage areas of the materials and referring to certain temperatures between 30 ℃ and 150 ℃. Composite materials are lightweight; they show high strength. For these reasons, they are preferred in technology, especially in the aircraft and aerospace industry. With this study, the radial and tangential stresses determined within a certain temperature The temperatures were determined and compared with previous studies in the literature. According to the results obtained, it is believed that the thermoplastic composite CF/PA6 disc design can be used in engineering.
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