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"Air Traffic Control (ATC) tasks require a high mental workload with complex cognitive activities. Since the tasks are likely to be fatigue-inducing and may cause aircraft accidents, ergonomics interventions are needed. This study investigated the effectiveness of peppermint odor on improved performance and fatigue while conducting simulated ATC tasks. A total of 16 participants performed ATC tasks using SkyHigh simulation software for two hours in two conditions (with and without peppermint odor). While the simulator was able to record participants’ performance during ATC tasks, participants’ fatigue development was monitored using an electroencephalograph (EEG), a heart rate monitor (HRM), and psychomotor vigilance task (PVT) apparatus. The results of this study show that the use of peppermint odor significantly (p < 0.05) improved simulation performance, based on all simulation indicators. The peppermint odor also significantly (p < 0.05) inhibited fatigue development, based on an EEG measure (decline in parietal ?), two HRM measures (decline in low frequency power (LF) and increase in high frequency power (HF)), and a PVT measure (10% of the longest time reaction)."

"Ballast is one of themain structures for the railway tracks. It can resist the lateral movementunder dynamic loading transferred by the passing trains with repeatedly. Undersome circumstances, ballast can suffer degradation or breakdown due to therepeated loading and maintenance. Ballast is easily exposed to the weatherbecause it is laid on the track. Acid rain affects the performance of therailway track near the industrial and urbanarea. As a result, it starts to foul and the small chips from ballast filledthe void, as well as reduce the shear strength of ballast particles. Thissituation can contribute into the increasing of maintenance frequency andcosting. This paper examines the potential of rubber inclusions in increasingthe shear resistance of rubber-ballast composites in simulated water and acid soakedconditions with several configuration. This lab-based exploratory work is only static load simulation in conventional shear boxsetup measuring 60 mm × 60 mm.The aggregates size is 10 times smaller than actual size of ballast. In orderto identify the shear resistance deterioration of rubber-aggregates mixtureunder poor drainage conditions by soaked a batch of aggregates in water andacid solution for 2 weeks to simulate accelerated weathering effects. The shearresistance did not rise dramatically with the rubber reinforcement. Thissusceptible shear strain plots indicate ductile behaviour on theaggregates-rubber composites. This is evident by the linear rise of shearstress with strain up to approximately 10% for the control samples (CS) untilit reaches a constant value. Note that all the specimens including CS are in aloose state during the testing because there were no tamping been applied onthe samples. Overall the circular patch (CP) specimen was the most favourablethan the other configurations. Both mechanisms contributed to the reducedoverall subsistence, accompanied by an increase in the shear resistance. Theinclusion of rubber elements apparently prevented the dilation of the granularmaterial when approaching the shear failure and the reducing the settlement."

"Concreteis a favoured building material due to its ease of productionand use. Even though the concrete mix isdesigned to have a uniform strength throughout the entire member, casting, aswell as the basic characteristics of the concrete materials, could yield anon-homogeneous constitution, resulting in a concrete strength gradation as afunction of the depth of the member. A functionally continuous and smooth strengthgradation of the concrete member along its axis or section is defined as gradedconcrete. The objective of this researchis to analyse the influence of two different concrete compressivestrengths that composed the gradedconcrete member. Thestudy is split into two parts: theexperimental work describing and identifying the mechanical properties offunctionally graded concrete and the finite element analysis implementing theseproperty variations in a model. The results showed that the concrete gradationinfluenced the ultimate strength of a member negatively and altered the stressdistribution and displacement response of the specimen."

"The fixed jacket isstill the most common offshore structure used for drilling and oil production.The structure consists of tubular members interconnected to form athree-dimensional space frame, which can be categorized into a columnstructure. The structure usually has four to eight legs that are battered toachieve stability against axial compressive loads and toppling due to waveloads. The configuration of a typical member on the jacket structure hassignificant influence on buckling and fatigue strength. Horizontal and diagonalbraces play an important role in resisting the axial compression and wave loadon the global structure. Thispaper discusses the effect of symmetrical and asymmetrical configuration shapesin buckling and fatigue strength analysis on two types of fixed jacket offshoreplatforms. The axial compressive and lateral (wave) loads were considered andapplied to both structures. The material and dimensions of the two structureswere assumed to be constant and homogenous. Crack extension and corrosion werenot considered. To assess the buckling and fatigue strength of thesestructures, due to the symmetrical and asymmetrical configuration shape, thefinite element method (FEM) was adopted. Buckling analysis was performed onthese structures by taking two-dimensional planes into consideration to obtainthe critical buckling load for the local plane; fatigue life analysis was thencalculated to produce the fatigue life of those structures. The result obtainedby FEM was compared with the analytical solution for the critical bucklingload. The stress-strain curve was also applied to show the difference betweensymmetrical and asymmetrical shapes. For fatigue life analysis, the procedureof the response amplitude operator was applied."

"It is widely use ofair-conditioning systems in Thailand due to its location. It is located in atropical zone with relatively high temperatures all year round, with highhumidity and high intensity of sunlight. In order to save electrical energy forair-conditioning systems, preventing heat transfer into the building isrequired. The objective of this study is to investigate the physical andthermal properties of concrete blocks. An attempt is made to increase heatresistance of concrete blocks. Foam beads (0-0.30% by weight) and kaolin (0-70% by weight) wereadded in concrete block mixture to increase discontinuous voids in concrete.Compressive strength and water absorption of concrete blocks were tested. Thetesting results indicated that compressive strength decreased when foam beadsand kaolin were added. Water absorption increased when foam beads were added.In contrast, the more kaolin added the less water absorption. The thermalconductivity coefficient of concrete blocks was also investigated. The resultsconfirmed that the higher the amount of foam beads or kaolin added, the higherthe thermal resistance of concrete blocks. Thermal time-lag behavior was alsoinvestigated. The results indicated that concrete block with kaolin took thelongest time in heating and took the shortest time in cooling. These propertiesare good for heat prevention in hot climate regions. These concrete blockswhich were developed and tested in this research conform to the Thai IndustrialStandard. Finally, it can be concluded that because of its thermal behavior,concrete block with kaolin is a suitable energy-saving concrete block for hotand humid climates."

"As an initial analysis,numerical simulation has more advantages in saving time and costs regarding experiments. For example, variations in flowconditions and geometry can be adjusted easily to obtain results. Computationalfluid dynamics (CFD) methods, suchas the k-ε model, renormalizationgroup (RNG) k-ε model and reynolds stress model (RSM), are widely used toconduct research on differentobjects and conditions. Choosing the appropriate model helps produce and developconstant values.Modeling studies as appropriate, i.e., in the turbulent flow simulation in the windtunnel, isdone to get a more accurate result. This study was conducted by comparing the results ofthe simulation k-ε model, RNG k-ε model and RSM, which is validated by the testresults. The air had adensity of 1,205 kg/m3, a viscosity of 4×10-5 m2/sand a normal speed of 6 m/s. By comparing the simulation results of the k-ε model, RNG k-ε model and RSM, which isvalidated by the test results, the third turbulencemodel provided good results to predict the distribution of speedand pressure of the fluid flow in the wind tunnel. As for predicting theturbulent kinetic energy, turbulent dissipation rate and turbulent effectiveviscosity, the k-εmodel was effectivelyused with comparable results to the RSM models."

"Wireless 3.5G is designed to deliver various kind of multimedia packages through IP network. Quality of Service (QoS) fulfilment is a crucial factor for multimedia applications...."

"The combination ofbaffled air flotation and a membrane system for the treatment of palm oil milleffluent (POME) was studied. The POME was obtained from a palm oil factory inPTPN I Tanjong Seumantoh, Aceh, Indonesia. Operation variables and conditions,such as the hydraulic retention time and air flow rates, were varied to findthe optimum process. The air flotation process is able to reduce theconcentration of suspended solids and fats/ oils contained in the wastewater,which increases the performance of the membrane by reducing clogging. Theresults showed that this method was promising for POME treatment. The optimumorganic removal efficiency of the air flotation pretreatment was obtained atHRT = 5 days and at an air flow rate of 11 L/min. The effluent was subsequentlypassed through an anaerobic membrane system to achieve the highest removalefficiency treatment. The removal efficiency of chemical oxygen demand (COD),total suspended solids (TSS), turbidity, mixed liquor suspended solids (MLSS),mixed liquor volatile suspended solids (MLVSS), and fats/oils after passingthrough the membrane system were 97%, 93.9%, 99.8%, 94.5%, 96.2%, and 99.9%,respectively. The results also showed that the pH could be neutralized to 6.18,while a dissolved oxygen (DO) level of 1.60 mg/L could be achieved. A highquality of effluent was obtained, which met the standards for POME effluent."