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Integrated ethylene oxide/ethylene glycols (EO/EG) plants are prominent energy consumers in the petrochemical sector, particularly concerning high‐pressure steam (HPS) usage which holds the potential for substantial energy savings. This study focuses on an unexplored territory: Examining the impact of EO catalyst type, selectivity, and glycols production capacity on HPS import in a plant in the Pars Special Economic Energy Zone (PSEEZ). Utilizing Python3 for data preprocessing and ordinary least squares linear regression analysis, we evaluate how varying catalyst loads and production scenarios influence HPS import. Regression models are created, encompassing normal and efficient HPS import scenarios, yielding positive outcomes in terms of correlation, mean error percentage, and R2 analysis. Comparing normal and efficient HPS import models highlights potential savings, uncovering opportunities to conserve between 45 and over 200 tonnes per day of HPS. We also explore the plant's HPS behaviour under 1% selectivity and production capacity reductions. Notably, catalyst activity decline markedly escalates HPS import for hybrid catalysts, while selectivity decline decreases HPS import for high‐activity catalysts. The models demonstrate that HPS import is ~150 tonnes per day more sensitive to a 1% change in selectivity compared to production capacity. Moreover, when comparing high activity and hybrid catalyst scenarios in normal and efficient cases, the most substantial HPS import difference arises under conditions of low selectivity, amounting to nearly 200 tonnes per day. Our methodology applies to other EO/EG plants. It is incorporated into our plant's energy management system, enabling continuous monitoring of steam import behaviour relative to catalyst and plant performance. [ABSTRACT FROM AUTHOR]

Dust is an important atmospheric phenomena that occurs in spring and summer in many regions, including Iran and its neighboring countries. Considered one of the most important challenges of the last century, this phenomenon occurs on a global scale in arid and semi-arid regions. Because of changes in climate and vegetation as well as progressive processes of soil erosion and the disturbances resulting from them, the sensitivity of regions to rapid erosion will have important reactions on the region's climate and desertification. Therefore, the current research investigated the concentration and distribution of fine dust under the influence of meteorological parameters using the GCM climate model and attempted to determine the effect of climate change on the concentration of the relevant pollutant in the coming years. In this study, the CALPUFF model considered the temporal and spatial effects of weather conditions on the transfer, transformation, and removal of atmospheric pollutants. The emission rate of the PM10 pollutant was estimated. The results indicated that the increase in greenhouse gas emissions and changes in climate variables in the near future will cause the distribution of suspended particles one of the important pollutants to increase significantly. The results also revealed a significant relationship between the degradation of air quality and the trend of air warming during the period 2046-2065. [ABSTRACT FROM AUTHOR]

More attention has been paid to Damage detection in offshore jacket platforms (OJP) because of repair and maintenance issues. Damage detection using modal data from a few sensors is one of the main important subjects that researchers have paid attention to it. The inverse Vibration Problem (IVP) technique does not need modal data in all nodes of OJP but first modal data in different levels of platform and principal degrees of freedom could be sufficient. Since the complex structural model becomes a reduced shear building by implementing this technique, there must be a reduced equivalent stiffness matrix for the healthy structure to make the comparison for damage detection. This paper deals with the formulation and implementation of IVP technique in corporation of the proper method for calculation of equivalent level stiffness. The proper method was selected based on a comparison of modal data obtained from full and reduced models using comparison tools like the MAC coefficient. Also, damage detection in a typical OJP model under a specific damage scenario was investigated numerically and experimentally and the results show the reliable performance of the methodology. A damage detection flowchart is suggested to detect damage location properly. It is developed mainly based on geometrical couplings in OJP structure in damaged conditions and the method leads to damage location exactly and maximum error in damage prediction is obtained at about 12%. [ABSTRACT FROM AUTHOR]

Roll control of the Autonomous Underwater Vehicles (AUVs) is a significant issue in the current field of research for many researchers in the subject of AUV control system designation. Especially at higher speeds, the roll angle generated by a single rotating propeller or other external disturbances can considerably influence the whole dynamics and therefore the operation of the vehicle. In this paper, the utilisation of a system of contra-rotating-propellers (CRP) to enhance the roll dynamics of an AUV is evaluated by developing a six-degrees-of-freedom (6DOF) dynamics and control systems' simulator. The results show that: 1. The single propeller system can cause roll angle deflections affecting the heading angle and depth of AUV depending on the forward speed. 2. Using the contra-rotating system with a proper roll controller can enhance the roll dynamics of the vehicle, particularly for the real-time roll stabilisation and maneuvering goals. [ABSTRACT FROM AUTHOR]

Floating wind turbines are subjected to highly dynamic and complicated environmental conditions leading to significant platform motions and structural vibrations during operation and survival conditions. These motions and vibrations alter the induced loading characteristics; and consequently, affect the dynamic behavior of the system. In order to better understand the influence of such motions and structural vibrations, herein elastic structural disturbance of tower, on the system behavior, the spectral and statistical characteristics of a floating wind turbine dynamic responses under operational and survival conditions are fully explored using a fully coupled aero-hydro-servo-multi-rigid-flexible-body model. The spectral comparison results showed the important role of aerodynamic damping in reducing the high-frequency resonant responses in operational conditions. These analyses also revealed the effects of tower elasticity in shifting and amplifying high-frequency resonant responses. The statistical comparison results showed that the mean values of the responses are dominated by wind loads and the maximum and standard deviations of the responses are mainly induced by the combination of support platform motions and wave loads. It was also shown that elastic structural deformation of tower enlarges the statistical characteristics of the responses, especially when the system is subjected to both wind and wave loadings. [ABSTRACT FROM AUTHOR]