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"The Aluminum 7075 (Al 7075) alloy is a precipitation hardening material instead of a strain hardening material. These mechanical properties are of a particular microstructure obtained by thermo-mechanical treatments. Among other things, this is a complicated microstructure which is responsible for the mechanical performance. The evolution of the mechanical properties of aluminum alloys is dependent on aging time parameters after heat treatment. In this study, the material has undergone a tempering heat treatment followed by a series of tensile tests. The experimental data (tensile curves in three directions during maturation time) is used to describe the evolution of the mechanical characteristics in terms of loading directions and maturation time, denoted respectively as: Ψ and t. The tensile curves are the source of data to begin the problem of identifying the behavior law of studied material using Barlat?s model and Hollomon?s isotropic hardening law. Thus, from the identified parameters (anisotropy coefficients and hardening coefficients), the evolution of the Lankford coefficient, deformation rate and load surfaces during the maturation time for three load directions (0°: rolling direction, 45° and 90°) are described. This study allows optimizing the response of the aluminum alloy to plastic strains, resulting from forming processes measured against the best time during maturation and the best load direction."

"The Aluminum 7075 (Al 7075) alloy is a precipitation hardening material instead of a strain hardening material. These mechanical properties are of a particular microstructure obtained by thermo-mechanical treatments. Among other things, this is a complicated microstructure which is responsible for the mechanical performance. The evolution of the mechanical properties of aluminum alloys is dependent on aging time parameters after heat treatment. In this study, the material has undergone a tempering heat treatment followed by a series of tensile tests. The experimental data (tensile curves in three directions during maturation time) is used to describe the evolution of the mechanical characteristics in terms of loading directions and maturation time, denoted respectively as: ? and t. The tensile curves are the source of data to begin the problem of identifying the behavior law of studied material using Barlat’s model and Hollomon’s isotropic hardening law. Thus, from the identified parameters (anisotropy coefficients and hardening coefficients), the evolution of the Lankford coefficient, deformation rate and load surfaces during the maturation time for three load directions (0°: rolling direction, 45° and 90°) are described. This study allows optimizing the response of the aluminum alloy to plastic strains, resulting from forming processes measured against the best time during maturation and the best load direction."

"Transparent conducting oxide (TCO) glasses play an important role invarious technology, including dye sensitized solar cells. One of the mostcommonly used glass is indium tin oxide (ITO) glass, which is expensive.Therefore, the mainpurpose of this research was to determine if ITO glass can be replaced withfluorine-doped tin oxide (FTO) glass,which is easier and more economic to manufacture. For this purpose, a tinchloride dehydrate (SnCl2.2H2O)precursor was doped with ammoniumfluoride (NH4F) using asol-gel method and spray pyrolysis technique toinvestigate the fabrication process for conductiveglass. NH4F wasdoped at a ratio of 2 wt% in the SnCl2.2H2O precursor atvarying deposition times (10, 20, and 30 minutes) and substrate temperatures(250, 300, and 350°C). Theresults revealed that longer deposition times created thicker glass layers withreduced electrical resistivity. The highest opticaltransmittance was 75.5% and the lowest resistivitywas 3.32´10-5 Ω.cm,obtained from FTO glasssubjected to a 20-minute deposition time at deposition temperature of 300oC."

"The kinetics of aluminumleaching from sludge solid waste (SSW) using hydrochloric acid at differentleaching temperatures (30-90°C) was studied. A mathematical model was developed based on ashrinking core model by assuming first-order kinetics mechanisms for leachingand an equilibrium linear at the solid-liquidinterface. The proposed model is suited to fit experimental data with threefitting parameters and to simulate the leaching of aluminum from SSW, which wasvalidated with the mass transfer coefficient (kc, cm/s),diffusion coefficient (De,cm2/s), and reaction rate constants (k, cm/s). The evaluated kc,De, and k are expected to follow an increasingtrend with increasing temperature. The correlation coefficient ≥ 0.9795, theroot mean square error ≤ 0.399, the mean relative deviation modulus ≤ 6.415%,and the value of activation energy is 13.27 kJmol-1. The proposed model could describe the kinetics ofaluminum leaching from the SSW DWT in accordance with test parameters andrelevant statistical criteria. Valuable information on the results of this workcan be given for the purposes of the simulation, optimization, scaling-up, anddesign of the leachingprocess."

"Due to criticalenvironmental issues, increasing future energy supplies and decreasing reservedenergy resources are currently the subject of comprehensive research. The useof biomass as a renewable energy resource may be helpful in solving currentenergy shortfalls, particularly for countries that have abundant biomassresources. In this study, pyrolysis of coal, Acacia Mangium wood, and their respective blend samples wereinvestigated using proximate analysis and Thermogravimetric (TG?DTG). A mixtureof coal and A. Mangium wood with aweight ratio 100:0, 90:10, 50:50, 10:90, and 0:100, were used andnon-isothermal conditions at a constant heating rate of 5, 15, and 30°C/minwere applied. Thermal evolution profile analysis of the pyrolysis processconfirms that the reactivity of the fuel increased with the increasingproportion of the biomass in the fuel. The reactivity and maximum temperaturesincreased with the increasing heating rates. Proximate analysis showed thepotential of biomass of A. Mangiumwood to be used as a mixture with coal in terms of low ash and high volatilematter content."

"The definition of the physical and mechanicalproperties of sugarcane trash pellets were necessary for the designconsiderations relating to storage, handling andprocessing equipment. The mixing ratios of groundsugarcane trash:cassava starch:water content (1.0:0.25:0.85 and 1.0:0.25:1.40 by weight) and pelleting speeds (100, 120, 140, and 160 rpm) were considered to determine their effects on bulkdensity, true density, porosity, durability and compressive strength. The results show that the mixing ratio byweight of 1.0:0.25:0.85 and pelleting speed of 120to 140 rpm were optimum for producing the sugarcane trash pellets. At the moisture content of 12.01% (wb), the bulk density, true density, durability and compressive strengthof biomass pellets were in the range of 330.93 to 365.00 kg/m3, 860.38 to 918.43 kg/m3, 99.34 to 99.46 % and 5.15 to 6.43 MPa, respectively."

"Research and development activities on Liquefied Petroleum Gas (LPG) vehicles have increased LPG engine performance to that of gasoline engines. LPG evaporation in the fuel system also has a potential cooling effect that can be taken advantage of. The results from previous studies, however, do not explain the level of fuel in the tank at the time of data collection. LPG is a mixture of several molecules which have different properties. This paper presents an investigation of LPG composition characteristics in the fuel line during the discharging process. Samples were taken periodically on the fuel line by special gas syringes. Afterwards, the samples were injected into the Gas Chromatography-Mass Spectrometry (GC-MS) device. This series of tests, which was conducted on lengthy LPG tanks, showed that the propane and butane 2-methyl molecules are unevenly dispersed during the discharging of the tank. However, this study found that a change in LPG composition during the discharging process does not have significant influence on the energy delivery and the potential cooling effect."

"In recent times, thedemand for the real time audio and video applications in wireless networks isvery high due to widespread use of latest wireless communication technologies.Many of these applications require different Quality of Service (QoS) in termsof delay and throughput in the resource constrained wireless networks. In orderto handle the resources effectively and to increase the QoS, proper packetscheduling algorithms need to be developed. Low-latency Queuing (LLQ) is a packet scheduling algorithm whichcombines Strict Priority Queuing(SPQ) to Class-Based Weighted Fair Queuing (CB-WFQ). LLQ places delay sensitive applications suchas voice and video in the SPQ and treat them preferentially over other trafficby allowing the application to be processed and sent first from the SPQ. In this paper, an Enhanced LLQ (ELLQ) is proposed.An additional SPQ is introduced for scheduling the video applicationsseparately along with the dedicated SPQ for voice applications. The performanceof the proposed algorithm is compared with other existing algorithms throughsimulations using the OPNET modeler. Simulation and Statistical results showthat the proposed algorithm has given 1.5 times performance improvement interms of throughput and delay than the existing algorithms for the real timeaudio and video applications."

"The effectiveness of transportation demand management policy depends on how commuters respond to it. This study attempts to comprehend commuter behavior in choosing routes based on electronic road pricing (ERP) policy implementation on the Sudirman and Kuningan corridors. The experiments were conducted using the data collections from a stated preference experiment in which each commuter makes a route choice with an alternative representing a hypothetical situation with a combination of tariffs and travel time in ERP policy implementation. Logit models found that the individual and household variables influence route divert behavior. A commuter with a higher income or more family members living together is more likely to have less flexibility in diverting route. In addition, the distance of the trips affected their route divert behavior and influenced an individual trip chain constrained in time-space prism."