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"Cold formedsteel has relatively high width-to-thickness ratio elements, which causes it tobuckle easily. Combining it with timber laminas would be an effective solutionfor reducing this buckling problem. This research focuses on the connectionsystem of a cold formed steel-timber composite, which was obtainedby attaching several timber laminas to the web part of cold formedsteel using screws. The connection used two bolts that were 8 mm in diameter,as well as two different kinds of side plates: steel and plywood. Cold formedsteel 75Z08 and Swietenia mahagoni(moisture content 12.2%; specific gravity 0.77) were used for connections andwere loaded in parallel and perpendicular directions. In addition, theconnections of cold formed steel (without timber laminas) usingself-drilling screw fasteners were tested until failure. Numerical analysispredicting the load-slip curve and apparent yield load of the composite joints wascarried out using the DOWEL program and the European Yield Theory,respectively. The test results showed that the connection system with steelside plates is capable of accommodating the strength increase of compositemember, as it has a maximum load carrying capacity and initial slip modulus ofabout 4.5 and 2 times larger than those of the cold formed steel connections, respectively. In the caseof a connection system with plywood side plates, its joint properties aresimilar to those of the cold formed steel connection, except that it has largerjoint deformation."

"Cold formed steel has relatively high width-to-thickness ratio elements, which causes it to buckle easily. Combining it with timber laminas would be an effective solution for reducing this buckling problem. This research focuses on the connection system of a cold formed steel-timber composite, which was obtained by attaching several timber laminas to the web part of cold formed steel using screws. The connection used two bolts that were 8 mm in diameter, as well as two different kinds of side plates: steel and plywood. Cold formed steel 75Z08 and Swietenia mahagoni (moisture content 12.2%; specific gravity 0.77) were used for connections and were loaded in parallel and perpendicular directions. In addition, the connections of cold formed steel (without timber laminas) using self-drilling screw fasteners were tested until failure. Numerical analysis predicting the load-slip curve and apparent yield load of the composite joints was carried out using the DOWEL program and the European Yield Theory, respectively. The test results showed that the connection system with steel side plates is capable of accommodating the strength increase of composite member, as it has a maximum load carrying capacity and initial slip modulus of about 4.5 and 2 times larger than those of the cold formed steel connections, respectively. In the case of a connection system with plywood side plates, its joint properties"

"This paper reports onthe investigation of thermal properties of Kapok, Coconut fibre and Sugarcanebagasse composite materials using molasses as a binder. The composite materials were moulded into12 cylindrical samples using Kapok, Bagasse, Coconut fibre, Kapok and Bagassein the ratios of (70:30; 50:50 and 30:70), Kapok and Coconut fibre in theratios of (70:30; 50:50 and 30:70), as well as a combination of Kapok, Bagasseand Coconut fibre in ratios of (50:10:40; 50:40:10 and 50:30:20). The sample size is a 60 mmdiameter with 10?22 mm thickness compressed at a constant load of 180 N using a Budenbergcompression machine. Thermal conductivity and diffusivity tests were carriedout using thermocouples and theresults were read out on a Digital Multimeter MY64 (Model:MBEB094816), whilea Digital fluke K/J thermocouple meter PRD-011 (S/NO 6835050) was used to obtain thetemperature measurement for diffusivity. It was observed that of all the twelvesamples moulded, Bagasse, Kapok plus Bagasse (50:50), Kapok plus Coconut fibre(50:50) and Kapok plus Bagasse plus Coconut fibre (50:40:10) has the lowestthermal conductivity of 0.0074, 0.0106, 0.0132, and 0.0127 W/(m-K) respectivelyand the highestthermal resistivity. In this regard, Bagasse has the lowest thermalconductivity followed by Kapok plus Bagasse (50:50), Kapok plus Bagasse plusCoconut fibre (50:40:10) and Kapok plus Coconut fibre (50:50)."

"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."

"Batteries on the markettoday still use liquid-type electrolytes, which can result in safety issuescaused by electrolyte leakage. Therefore, studies that search for solid-stateelectrolytes are important for resolving these issues. In this research, acomposite of lithium phosphate-montmorillonite-polyvinylidene fluoride (Li3PO4-MMT-PVDF)has been characterized with the aim of detecting the electrochemicalperformance of Li3PO4 with the addition of MMT. Li3PO4samples were prepared through a solid-state reaction, which was then mixed with MMT, which hada composition ranging from 5 wt% to 20 wt%, and 1 wt% PVDF as a binder. Thischaracterization was conducted with structural, morphological, andelectrochemical aspects. The structural test showed that the X-ray diffraction (XRD) pattern was dominated by Li3PO4 peaks and MMT aluminosilicates. The electrochemical characterization indicatedthat the conductivity value of the composites was greater than that of Li3PO4.The highest conductivity was achieved with a 15 wt% MMT addition, with adielectric-constant value of 74.9 at a frequency of 10 kHz."

"The present work aims to improve the microstructure and hardness relatedproperties of age hardened Al6061-SiC reinforced composites produced by a two stage stir casting method. Three composites with2, 4, and 6wt. % (35-40μm) of SiC reinforcement are subjected tomicrostructural examination and hardness test at different locations to analysethe uniform distribution of the reinforcements in the matrix. As-castcomposites are solution-treated at 558°C, followed by an aging treatment conducted at 100, 150, and 200°C, during which peak hardness values are noted. The peak agedsamples are subjected to hardness and wear tests. In line with the objectives, ranges from 80-100% and 120-145% additional increase in hardnessvalues are observed over as-cast alloy during the aging treatment conducted at 100, 150 and 200°C, respectively. Lower temperature aging showssubstantial improvement in hardness and wear resistance over high temperatureaging in each respective group. Alsohigher weight percentages of reinforced composites show excellent wearresistance, due to the presence of eroded iron particles fromthe counter surface which is regarded as a beneficial effect during the wear test. The presence of SiC particles provides more sites for the nucleation of fineprecipitates. These fine precipitates hinder the movement of dislocation andthus increases hardness as well as wear resistance after the precipitation hardening treatment."

"Knowledge-Growing system (KSG) is a system that is capable of growing its knowledge along with the accretion in information as the time passes and uses it as the basis of making a decision. the knowledge growing mechanism in the system is performed by using observation multi-time A3s (OMA3S) information-inferencing fusion method. the smallest structure of KGS is an inteligent agent. "

"The choice among modes of intercity transport depends on conditions of not only intercity transport modes but also intracity transport in both the departure city and the arrival city. Intracity transport conditions might be advantageous for one intercity mode and disadvantageous for others. Intercity and intracity transport conditions are complex and need to be approached systemically. This study proposes an approach based on the passengers? preferences. The logit model was adapted to evaluate the transport modes? choices in competition. This model is called the ?Adapted Mixed Multinomial Logit Model? (AMML). It was applied on the Jakarta-Bandung corridor in both directions. It contributes to a complete approach for intercity transport mode choice by considering the influence of the intracity transport conditions in both the departure and arrival cities. The results proved that the choice of intercity transport mode depends not only on its own quality of service but also, importantly, on that of the intracity transport systems."

"The infrastructure of the transportation system plays an important and strategic part in the development of a country and serves to support economic progress by enabling the mobility of citizens and the distribution of goods from one region to another. However, communities have unequal access to the system and there are gaps in the regional infrastructure in Indonesia, leading to the requirement for a mapping of all 33 provincial capitals. In this study, we reviewed provisions for road, sea, air, and rail travel. The mapping result is expected to determine the pattern and the prioritization needed for future infrastructure development. A literature review was performed to establish assessment indicators for the mapping. The weighting of each indicator was based on a survey of stakeholders in transportation sectors, which was then analyzed using the Analytical Hierarchy Process. After weighting was completed, the infrastructure of each provincial capital was assessed to determine ratings from the highest to the lowest rank. Jakarta, Medan, Bandung, Surabaya, and Semarang obtained the highest rankings, while Manokwari, Serang, Mamuju, Ternate, and Palangkaraya were at the bottom. This result shows that provincial capitals in western Indonesia had better assessment results than those in the east. Therefore, improvements to the transportation infrastructure of the latter cities should be prioritized."

"The findings of numerousstudies on the responses of stream quality indicatorsto different levels of watershed development have been integrated into an impervious cover model. The focus on one development stressor, namely theimpervious cover, allows the decision makers to use the impervious cover model as a watershed planning toolto forecast stream response. In evaluating streamquality, the studies used various indicators such as pollutant loads, habitatquality, aquatic species diversity and abundance, and others. This studyaims to test the applicability of the imperviouscover model as a tool to set the threshold of catchment area developmentbased on the targeted water quality index. Themodel is represented by a linear relationship between the water quality indexas a response variable and catchment area imperviousness as an explanatoryvariable. The study area is an urbanized catchment area of a cascade-pondsystem located at the campus of Universitas Indonesia, Depok, West Java.Estimation of catchment area imperviousness is based on digital globe imageryand digitized based on identified rooftops. The water quality data to computethe water quality indices are collected from previous studies and relatedreports. The targeted water quality index is determinedbased on water use suitability referring to the Indonesian governmentregulation number 82/2001. Basedon the available data, an increasing tendency of temporal variation ofcatchment area imperviousness for each pond can be recognized, while waterquality index of each pond tends to decrease over time. In accordance with landcover distribution, spatial tendency indicates that imperviousness isdecreasing in downstream direction, while water quality index is increasing indownstream direction, in line with the characteristics of cascade ponds. Theresults demonstrate that despite the fact that the available data are verylimited, it is possible to use the linear relationship between catchment areaimperviousness and water quality index as a tool to set the threshold forfuture development on the catchment area of the cascade-pond system at thecampus of Universitas Indonesia with a minimum water quality index suitablejust for recreation activities."