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This study systematically investigates the impact of image enhancement techniques on Convolutional Neural Network (CNN)-based Brain Tumor Segmentation, focusing on Histogram Equalization (HE), Contrast Limited Adaptive Histogram Equalization (CLAHE), and their hybrid variations. Employing the U-Net architecture on a dataset of 3064 Brain MRI images, the research delves into preprocessing steps, including resizing and enhancement, to optimize segmentation accuracy. A detailed analysis of the CNN-based U-Net architecture, training, and validation processes is provided. The comparative analysis, utilizing metrics such as Accuracy, Loss, MSE, IoU, and DSC, reveals that the hybrid approach CLAHE-HE consistently outperforms others. Results highlight its superior accuracy (0.9982, 0.9939, 0.9936 for training, testing, and validation, respectively) and robust segmentation overlap, with Jaccard values of 0.9862, 0.9847, and 0.9864, and Dice values of 0.993, 0.9923, and 0.9932 for the same phases, emphasizing its potential in neuro-oncological applications. The study concludes with a call for refinement in segmentation methodologies to further enhance diagnostic precision and treatment planning in neuro-oncology.

High-Strength Self-Consolidating Concrete (HSSCC) is a type of concrete that possesses superior mechanical properties and can self-settle without the need for vibration assistance. Numerous advancements have been implemented to enhance the properties of HSSCC. In prior experimental work, the authors investigated the mechanical characteristics of HSCC with 12.5% metakaolin and 0-15% silica fume as a partial cement substitute. Since metakaolin and silica fume have smaller particle sizes than cement, they can fill voids between aggregate and enhance the concrete’s compactness. Further structural study is necessary to provide a more complete knowledge of the impact of partially substituting cement with metakaolin and silica fume. Using the Response 2000 program, this investigation analyzes the shear behavior of reinforced HSSCC beams. Laboratory-determined material mechanical properties were utilized as simulation input data. In this investigation, the maximum strength, deflection, and crack development of five beam models produced with varying material mechanical properties were investigated and compared.

The study of the food and feeding habits of fishes is crucial in understanding their ecology. Food and feeding habits of the 30 fish species belonging to 22 families from Bukit Sari and Awat-awat of Lawas in the Bay of Brunei were studied on 11th February 2020 and 12th February 2020 respectively. Samples were collected using “Kabat” nets, casting nets, and seine nets. The dietary components of each species were studied and expressed as a percentage of numerical composition (N), percentage of weight composition (W), and percentage of frequency of occurrence (F). Diet compositions of the species were estimated using the Index of Relative Importance (%IRI) and trophic level (TROPHj). The major food and their Index of Relative Importance (%IRI) showed the highest was shrimps (64.25%) followed by crabs (11.78%), zooplankton (6.94%), fish (6.91%), algae (4.21%), plants (1.48%), mollusks (1.01%) and others below 1.0%. TROPHj value ranged from 2.0 to 4.2 and the trophic level value of 25 fish species was carnivorous, followed by 2 species (detritivorous and herbivorous) respectively, and 1 species (piscivorous). The findings of the study may offer important data for developing management plans for the region's fishing resources.

On September 21, 2020, the Pasar Wage Building of Kabupaten Banyumas was hit by a fire causing spalling of the concrete and thus exposing the steel reinforcement. This damage can affect the performance and safety of the building. For this reason, an evaluation is needed to determine the performance of the post-fire structure to propose the necessary repair and retrofitting. Investigation and testing in the field were carried out in this study as primary data for seismic performance analysis. Static pushover analysis was carried out to provide information about the structure's collapse performance using damage states of the FEMA P-58 criteria. The seismic performance was then presented with a fragility curve to illustrate the probability of building damage. The results show that the maximum base shear value is 3033 kN with a displacement of 0.063 m. At a target displacement of 0.027 m, the base shear is 2618 kN. The probability of structural damage within a category of extensive is 77% if an earthquake at the Design Basic Eartquake (DBE) level strike the building. The probability of structural damage becomes 50% extensive and 50% complete at the Maximum Considered Earthquake (MCE) level.

A tsunami in Aceh in 2004 resulted in many casualties and damage to educational facilities. The disaster taught about the importance of preparedness in anticipating disasters to humans. It will help in shaping and planning what actions need to be taken in the event of a disaster. This study aimed to see the level of preparedness of the school community in Lhokseumawe City in dealing with the tsunami disaster. School community preparedness was measured using preparedness parameters, namely knowledge, and attitudes; policies and guidelines; emergency response planning; disaster warning system; and resource mobilization. This research is descriptive quantitative research employing a survey method using a closed questionnaire. Utilizing the descriptive percentage method, the research shows that the school community's preparedness in Lhokseumawe City is in the almost ready category with an index value of 57.02. The index value is obtained by adding up the index values for each parameter by taking into account its weight. The index value of the knowledge and attitude parameter of the school community; and the level of school community policies and guidelines are in the ready category with index scores of 68,24 and 65. School community emergency planning parameters; the level of the school community disaster warning system and the level of resource mobilization are in the unprepared category; not yet ready and almost ready with index values of 35.6; 40; and 54.15 respectively.

In order to achieve satisfactory global seismic behaviour of a concrete fame structure and to prevent undesirable local failures of its structural element, local strengthening of structural members by means of FRP wrap is one of the cost effective retrofitting strategy. This FRP wrapped column will increase the ductility of the element as well as the capacity that in turn will allow attaining more energy dissipating global performance. This on-going research aims to demonstrate the seismic performance of Low-to-Mid-Rise Concrete Frame retrofitted by FRP wrap in several configurations. The fragility curves of the structure before and after to local strengthening will be developed and analysed. Fragility curve will describe the probability of the structure that will exceed certain damage states given the ground shaking intensity during its service life. This curve allows evaluation for the retrofitting strategy is carried out rationally.

Sustained load problems, which can cause excessive deformation and severe damage to concrete structures, have been considered in current worldwide design codes by applying reduction factors on the compressive and tensile strength of concrete. A reduction factor in the shear design may also be required due to the decrease of shear-transfer action corresponding to the increases of the shear cracks opening. However, only a few studies are examining the effect of creep on shear performance of concrete structures, and the results are still inconclusive. As a complement to the previous experimental works, this study aims to investigate the effect of loading rate on the shear capacity of RC slender beams by non-linear finite element (FE) analysis. A spaceaveraged constitutive model with fixed multi-directional cracks was employed in the simulation of diagonal shear failure. The present study analytically examines the time-dependent effects on the beams under different loading rates until the delayed failure and compares the results with the previous experimental ones.

The main objective of this study is to evaluate the effect of nanosilica (NS) concentration on the rutting parameter of based asphalt binder using the multiple stress creep and recovery (MSCR) test. NS with concentrations between 1% to 5% (1% increment) was used to modify asphalt binder. The nanosilica modified asphalt binder (NSMB) were aged using rolling thin film oven (RTFO) before tested. MSCR test was conducted at 64°C with two stress level (100 Pa and 3200 Pa). The results found that the addition of NS reduced the accumulative strain of NSMB. Besides that, non-recoverable creep compliance decreased and recovery strain increased, which indicates an improvement of rutting resistance and elasticity of the binder, respectively. The grade of asphalt binder also improved from heavy (H) grade to extreme (E) grade. Overall, NSMB 2% show the best improvement in terms of Jnr and %R, thus NSMB 2% considered as a optimum percentage.

Hydropower generation is one of the key element in the economy of a country. The present study focusses on the optimal electricity generation from the Mangla reservoir in Pakistan. A mathematical model has been developed for the Mangla hydropower station and particle swarm and genetic algorithm optimization techniques were applied at this model for optimal electricity generation. Results revealed that electricity production increases with the application of optimization techniques at the proposed mathematical model. Genetic Algorithm can produce maximum electricity than Particle swarm optimization but the time of execution of particle swarm optimization is much lesser than the Genetic algorithm. Mangla hydropower station can produce up to 59*109 kWh electricity by using the flows optimally than 47*108 kWh production from traditional methods.