bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prompt analysis of condition priority for road improvement planning
Authors: Buchari E , Oktaviansyah D , Putranto D D A P , Nawawi N 
Published: May 2019

Abstract
The need for quick analysis for road pavement survey is inevitable, especially in a developing country. A new data collection method by using small format photo, which is recorded by drone is developed. The function of drone is not only for photographic purposes, but also developed to measure and record road damage. Digital aerial photogrammetric methods are developed faster than before. A small format areal imagery based on pixel size is developed for this study, so that the degree of road damage can be obtained quickly. In order to obtain a maximum pixel size to detect a maximum damage level of 1 cm, the shooting is done at a height of 24 m drone from the road surface. The result of road damage measured by measuring distance through image is then tested based on the measured sample, directly in the field with a trust level of 97.83%. These results show that the accuracy of road damage measurements made above high resolution photo images is very effective for data collection of road damage. Analysis of Condition Priority can be obtained in one day in complement with contour map and road level, while in previous time it is done within a week without contour map and level.
Development of operation and maintenance sustainability index for penarafan hijau jabatan kerja raya (pHJKR) green road rating system
Authors: Adzar J. A. , Zakaria R. , Aminudin E. , Rashid M. H. S. A. , Munikanan V. , Shamsudin S. M. , Rahman M. F. A. , Wah C. K. 
Published: May 2019

Abstract
The significant impact of infrastructure projects on the environment has created needs to assess its sustainability and responsiveness which indirectly respond to carbon emission reduction. A rating system is widely utilized as a tool to analyze the sustainability of buildings or infrastructures. Malaysia is one of the advanced nations which applies in road green rating system, whereby two rating systems for roads are established; MyGHI for highways and pHJKR (Roads) for non-tolled roads. Preliminary study on pHJKR (Roads) identified that this rating tool assesses road sustainability performance only at planning, design & construction stages. Since the establishment of pHJKR (Roads), no re-assessment has been carried out after the roads begin to operate. Whilst in sustainability resiliency, it is important to sustain its engineering and enhance its performance and services including carbon assessment, under operation and maintenance (O&M) of roads. This paper highlights the methodology of development for assessment criteria and elements during the operation and maintenance phase. The methodology leads to proposed score development which later will be used in association to index indicator for O&M pHJKR (Roads). The data for this study is gathered and analyzed from a comprehensive review of current pHJKR (Roads) with a comparison made to national and cross-nation green road rating index. An expert panel discussion will also be utilized as a method of verification in order to identify suitable sustainability factors during O&M. The outcome of the study will be proposed for the enhancement of pHJKR (Roads) with assessment criteria for operation and maintenance phase and eventually leads to the establishment of multiple life cycle phases for pHJKR (Roads).
Recycled concrete aggregate as a road base material
Authors: Giwangkara G. G. , Mohamed A. , Khalid N. H. A. , Nor H. M. , Hainin M. R. , Jaya R. P. , Sani W. N. H. M. , Ismail C. R. , Aziz M. M. A. 
Published: May 2019

Abstract
Natural crushed aggregate (NCA) is the most common material for aggregate throughout the world. The consumption of the NCA itself is rising up through the years. Concrete structures and road construction are some of the most consuming aggregate material, especially NCA. Therefore, aggregate such as recycled concrete aggregate (RCA) has become an alternative material for some particular civil construction. The implementation of RCA as road construction material has been raised for a long time ago especially in road base layer. Road base layer as foundation for road pavement must provide an adequate strength to hold the working load on the pavement surface. RCA is more heterogeneous material compared to NCA as the RCA contain many substances, such as aggregate, cement, sand, and some additive substances. Hence, it effects the strength of the RCA as construction material. In this paper, the properties of the RCA are investigated to get the characteristic of the aggregate. Density, water absorption, aggregate crushing value (ACV), compaction, and penetration test (CBR) were conducted in this research. An improvement by using plastic strips as addition also proposed to strengthen the RCA as road base material.
Properties of bitumen modified with latex
Authors: Daniel N. H. , Hassan N. A. , Idham M. K. , Jaya R. P. , Hainin M. R. , Ismail C. R. , Puan O. C. , Azahar N. M. 
Published: May 2019

Abstract
A lot of effort has been made to improve the base bitumen properties by adding different types of modifier. The current issue of pavement failure has raised a concern that high specification of bitumen is essential to counter the asphalt pavement challenges. This is to ensure that the bitumen could perform better as a road material. Natural rubber, particularly latex, has potential to be used as a modifier in bitumen compared to other types of rubber as it is cheaper, accessible and easily dispersed in the liquid bitumen when heated. This study evaluates the physical and rheological properties of the bitumen when added with latex rubber. Difference percentages of latex i.e. 2.5%, 5.0%, 7.5% and 10% were added to the 60/70 PEN bitumen and tested for penetration, softening point, viscosity, ductility, loss on heating and dynamic shear rheometer tests. As a result of the modification, it was found that latex hardened the control bitumen, increases the viscosity and provides better resistance against rutting.
Field performance of asphalt pavement maintenance using Cup Lump Rubber Modified Asphalt (CMA)
Authors: Razali R. , Hainin M. R. , Hassan N. A. , Idham M. K. , Malek M. S. C. , Warid M. N. M. , Yaacob H. , Mohamed A. , Ismail C. R. 
Published: May 2019

Abstract
It was typical in Malaysia that pavement failures at high stressed area were due to the bituminous layer aging subjected to extreme long loading times by the slow moving of heavy commercial vehicles. This scenario causes major structural deteriorations and permanent deformation of the bituminous road surfacing. In order to fix this problem, the used of Polymer Modified Asphalt (PMA) in asphalt mixture to form PMA mixtures was selected as an alternative method to increase the durability and lifespan of the pavement. PMA had been observed for a long time in improving the performance of asphalt pavement and increase the pavement lifespan. Although, it significantly improves the quality of the asphaltic layer and prolongs the life of the pavement, the construction cost was very high. Cup lump rubber was referred to the natural rubber in frozen form and it had been used as an additive in the conventional asphalt to produce cup lump modified binder (CMB). The mixture of cup lump modified binder with aggregates will produce the cup lump modified asphalt (CMA). Recently, Public Work Department of Malaysia and Malaysian Rubber Board recently had been conducted a field study at several locations to identify the benefits and CMA levels of performance as well as the constructability of the CMA pavement in actual field site. The monitoring and testing elements in this research were including mix design, construction methods and performances monitoring. The results have been showed that the performance of CMA was not shown significant improvement as compared to conventional asphalt section after six-month construction. From the result, it was noted that the longer observation period was needed to identify the actual field performance of cup lump asphalt pavement compared to the conventional asphalt pavement.
Transportation mode choice binary logit model: a case study for Johor Bahru city
Authors: Puan O. C. , Hassan Y. A. H. , Mashros N. , Idham M. K. , Hassan N. A. , Warid M. N. M. , Hainin M. R. 
Published: May 2019

Abstract
The mode choice stage in transportation planning is the analysis process to estimate the number or percentage of trips performed by each mode of transport. In practice, the number of trips is used to estimate the demand for each mode of transport. Such information is important for planning and designing transportation facilities in an urban area. A mathematical model of individuals’ mode choice is usually required in such an analysis. This paper discusses the result of a study carried out to evaluate the attributes that influence the mode choice of transport in Johor Bahru city by interviewing the individuals living for more than one year in the study area. The investigation conducted through one of attitudinal survey techniques known as stated preference survey. Stated preference survey conducted on a random sample of 384 respondents. Investigated attributes have been identified in analysis stage by applying binary logistic regression analysis procedure before deriving binary logit model for individuals’ mode choice of transport in Johor Bahru city. Based on stated preference survey and logistic regression analysis of data, the model of mode choice of transport in Johor Bahru has been derived and attributes of age, income, vehicle ownership, comfort of car, reliability of bus service, affective motives and instrumental motives were found statistically correlated to the mode choice of transport in Johor Bahru.
Parameters affecting fluctuation in traffic stream on urban roads
Authors: Al-Bahr T. M. , Puan O. C. , Hassan S. A. , Idham M. K. , Ismail C. R. 
Published: May 2019

Abstract
Moving Observer Method (MOM) is one of traffic data collection techniques that being used to collect the traffic flow at the urban roads. However, this technique is sensitive to the normal fluctuation of the traffic flow. Road length, intersection density, and driveway density are three main parameters contributed to the fluctuation of traffic flow in urban roads. This paper attempts to determine how much range of these parameters are affecting the fluctuation of the traffic flow. By using MOM technique, twenty urban roads in Johor Bahru city are selected randomly to analyse how these parameters contribute to this fluctuation of the traffic flow. Regression analysis is performed to identify the range of the effect of these parameters on the accessibility and fluctuation rate of traffic flow in urban roads. It is found that driveway density is significantly affecting the fluctuation of traffic flow followed by road length.
Analysis of hexagonal paving block as a better paving shape
Authors: Rachmat M. , Salsabilla T. N. 
Published: May 2019

Abstract
Because of the raise of road infrastructure, the use of paving block pavement increases as well. One of the problems of using paving block is the shape of it which influences of its interlock. The soil deformation over pavement makes it defect easily causing the paving block surface becomes uneven and the soil settled. The aim of this research is to prove that hexagonal paving block is a better paving shape than the other shape of paving. Therefore, analysis comes to the advantage and disadvantage of the installation process and interlocking from any different shape of paving. In order to be able to analyse hexagonal paving shape as the most optimum shape, this research utilizes literature review as the methodology research, to analyse the calculation we used SAP2000, Plaxis, Interlocking and installation pattern. The conclusion from the analysed result of SAP2000 output, Plaxis output, Interlocking and pattern installation can be concluded that hexagonal paving block is the most optimum shape caused its best for lock the pavement and easy to install. Analysis results for moment of force of paving block 10 cm are obtained 201612.46 kg/cm for cube, 6764.09 kg/cm for hexagon, 67460.04 kg/cm for octagonal and 171363.84 kg/cm for rectangular Therefore the deformation results are obtained -0.632 cm for cube, -0.097 cm for hexagon, -0.109m for octagon, -0.355 cm for rectangular. Deformation of soil deflection caused by paving block pavement is obtained 5.21 cm for cube, 3.38 cm for hexagon, 3.43 cm for octagon, 4.45 cm for rectangular. From the analyse of moment and deformation, soil deflection, interlocking and paving block installation can be concluded that hexagonal paving block is a better paving shape of paving block.
Measurement of percent time spent following on two-lane highways: an exploration of spot and space-based methodologies
Authors: Ibrahim M. N. , Puan O. C. , Mustaffar M. 
Published: May 2019

Abstract
Percent Time Spent Following (PTSF) is used as a key performance measure for two-lane highways as recommended by the HCM2010. PTSF is the average percent of total travel time that vehicles must travel in platoons behind slower vehicles due to inability to pass. Despite its acceptance as performance indicator, PTSF is difficult to measure directly in the field. It is therefore estimated using a surrogate measure based on the spot percent of vehicles travelling with headways less than three seconds (3 s) at a fixed point. However, the application of the 3 s headways as the sole criterion in the surrogate measure is still contentious. On the basis of definition, PTSF is both spatial and temporal variable whereas its estimation is based on fixed point. It is therefore desirable to develop a spatial measurement approach for PTSF that takes into consideration of travel time. A new method was therefore developed for spatial measurement of PTSF using a test vehicle equipped with a GPS-based speed acquisition and video recording system. This study explores the spot and spatial measurement techniques of PTSF. The indicator was then measured using the two approaches concurrently. Data for the study were sampled from 18 directional segments of two-lane two-way highways in Johor and Pahang States, Malaysia. Subsequently, the estimates from these approaches were compared. On comparing the PTSF values from the spot and space-based approaches, it was discovered the latter approach produced lower values than the former in most instances. A statistical test of difference of means at 95% confidence level indicated that the estimates from the two techniques do not differ significantly. This implies that PTSF from spot measurement do not differ much from those based spatial approach developed in this study. Finding from this effort would at least substantiate the application of the spot-based PTSF measuring technique; an issue that has been debatable. It also serves as a response to the contentious issue, which has not received the desired attention from experts previously.
Estimation of critical gap at small roundabout
Authors: Azhari S. F. , Puan O. C. , Hassan S. A. , Mashros N. , Warid M. N. , Lopa R. S. 
Published: May 2019

Abstract
The gap acceptance theory is basically implied to describe the driver’s behavior in the minor stream at the entry of roundabout searching for a suitable gap at the major stream to merge. The critical gap is an important parameter in the gap acceptance theory. However, the critical gap cannot be measured directly on the field. One way to measure the critical gap is by measuring only the rejected and accepted gaps. This study attempts to determine the critical gap at small roundabout using three different methods namely Raff’s Method, Wu’s Method, and Simple Logit Method. The data is collected at a two-lane roundabout in Skudai – Johor Bahru at the morning and afternoon peak hour using video camera technology. Accepted and rejected gaps are then extracted from the recorded videotape. The accepted and rejected gaps obtained are analysed to determine the critical gap. The findings from the study reveal that the critical gap values from the three methods are almost similar, having a critical gap of 3.45s, 3.60s and 3.45s for Raff’s Method, Wu’s Method, and Simple Logit Method respectively.
Particle scale modelling of porosity formation during selective laser melting process using a coupled DEM – CFD approach
Authors: Aggarwal Akash , Kumar Arvind 
Published: May 2019

Abstract
Selective Laser Melting (SLM), the most popular metal additive manufacturing (AM) process, is well suited for making complicated parts which are difficult to manufacture by conventional manufacturing techniques. Currently, the main bottlenecks inhibiting the usage of the Selective Laser Melting (SLM) parts include the problems, such as porosity, low resolution, low surface finish quality and low build rate. In order to overcome the aforesaid problems, latest SLM machines are now being equipped with laser having small spot radius for enhanced resolution and surface finish, and high power to increase the build rate. The combination of high power and small spot radius leads to high energy density, exceeding the threshold value, resulting in transition of melting mode in the SLM process from conduction mode to keyhole mode and a formation of porosity due to collapsing of keyhole. In this study, high fidelity particle scale model is developed using open-source codes LIGGGHTS and OpenFOAM to understand the formation of porosity and to describe the physical phenomena (convection, melting, evaporation and solidification), melt flow dynamics and melting mode transition occurring in the SLM process.
The formation of Al6 (Fe, Mn) phase in die-cast Al-Mg alloys
Authors: Zhu Xiangzhen , Ji Shouxun 
Published: May 2019

Abstract
In aluminium alloys, iron is a common impurity as it is unavoidably picked up in practice. The excessive Fe is strongly prone to form various intermetallic phases. These Fe-rich intermetallics are generally brittle and act as stress raisers to weaken the coherence with Al matrix, therefore decreasing elongation. However, Fe addition in Al-Mg alloys may be beneficial because of the improvement in the yield strength with the scarification of ductility of die-cast aluminium alloys. The morphology of intermetallic phases has a vital effect on the properties of aluminium alloys. In the present work, the 3D morphology of Al6 (Fe, Mn) in die-cast Al-Mg-Mn alloys with different levels of Fe contents were revealed. The formation of Al6 (Fe, Mn) was also studied through crystal features and solidification behaviours.
Recent advances in the understanding of the role of vanadium carbonitride precipitation to improve surface edge cracking on continuous casting of blooms
Authors: Erdem Hornauer E , Grafe U , Plociennik U , Klos W , Reifferscheid M , Luettenberg M 
Published: May 2019

Abstract
This study aims in combining the material properties and numerical modelling techniques through practical application to provide understanding of surface edge cracking caused by V(C, N) precipitation to enhance the yield of the continuous bloom caster at ArcelorMittal Duisburg. The investigation for this work is carried out on three different micro-alloyed steel grades; one of them being the most crack sensitive 20MnV6. A process model is used which calculates the solidification process of the strand to design an optimum cooling strategy. Therefore, two cooling patterns are employed for the steel grade 20MnV6. Reduction of area values of the steel grades 20MnV6, 27MnSiVS6 and 38MnSiVS5 evaluated from hot tensile tests using a Gleeble simulator have been used as an indication in assessing steel’s cracking behaviour. Further precipitates have been analysed by SEM at ArcelorMittal. These laboratory results suggest that precipitation kinetics of V(C, N) influences the crack sensitivity of the micro-alloyed steel. The software MatCalc® is used to simulate precipitation for process parameters of continuously cast blooms at Arcelor Mittal Duisburg as well as the parameters of the Gleeble experiments. From these simulations the Zener pinning force (ZPF), resulting from V(C, N) particles on grain boundaries, is evaluated which can be used as a measure for the crack sensitivity. Using the values of the ZPF it is possible to identify the set of casting parameters of the steel grade 20MnV6 which lead to the minimum crack intensity on the surface of the blooms. Moreover it is possible to make a ranking list with respect to the ductility drop occurring in the Gleeble experiments for the analysed steel grades. The proposed statement is an issue for a continuing investigation of precipitation modelling.
Control of Solidification Pattern of Cast Irons by Simultaneous Thermal and Contraction / Expansion Analysis
Authors: Riposan I , Stan S , Chisamera M , Neacsu L , Cojocaru A M , Stefan E , Stan I 
Published: May 2019

Abstract
An experimental device conducts thermal analysis and volume change measurements in a single ceramic cup with cast iron quality as the variable. The recorded data are processed using specialized software. Experiments compare solidification patterns for white [WI], grey [GI] and ductile [DI] irons, to correlate the most important events between the cooling curves and contraction curves, to evaluate the sensitivity to shrinkage formation. All of the irons have similar values for initial expansion up to the start of eutectic freezing [0.437 – 0.443%]. Graphite formation promotes expansion [WI-0.002%, GI-0.109%, DI-0.596%], resulting a difference in the reached maximum expansion [WI-0.465%, GI-0.552%, DI-1.032%], placed between the end of eutectic recalescence and the end of solidification. Higher graphite expansion, greater the shrinkage sensitivity: open shrinkage increased while the density of a casting when considering total shrinkage and micro-shrinkage formation decreased. Prolonged graphitization at the beginning of eutectic reaction increased the expansion and, consequently, shrinkage sensitiveness. More graphite formation at the end of this stage also increased expansion, but this phenomena contributed to reduce of shrinkage level, due to the better access of liquid iron to compensate contraction holes. Special metallurgical treatments can favour a strong graphitization process at the end of solidification, with beneficial effects on the castings soundness.
Cellular-to-Dendritic and Dendritic-to-Cellular Morphological Transitions in a Ternary Al-Mg-Si Alloy
Authors: Brito C. , Nguyen-Thi H. , Mangelinck-Noël N. , Cheung N. , Spinelli J.E. , Garcia A 
Published: May 2019

Abstract
The study is focused on the influence of solidification thermal parameters upon the evolution of the microstructure (either cells or dendrites) of an Al-3wt%Mg-1wt%Si ternary alloy. It is well known that the application properties of metallic alloys will greatly depend on the final morphology of the microstructure. As a consequence, various studies have been carried out in order to determine the ranges of cooling rates associated with dendritic-cellular transitions in multicomponent alloys. In the present research work, directional solidification experiments were conducted using either a Bridgman (steady-state) device or another device that allows the solidification under transient conditions (unsteady-state). Thus, a broad range of cooling rates (Ṫ), varying from 0.003K/s to 40K/s could be achieved. This led to the identification of a complete series of cellular/dendritic/cellular transitions. For low cooling rate experiments, low cooling rate cells to dendrites transition happens. Moreover, at a high cooling rate, a novel transition from dendrites to high cooling rate cells could be observed for the Al-3wt%Mg-1wt%Si alloy. Additionally, cell spacing λC and primary dendritic spacing λ1 are related to the cooling rate by power function growth laws characterized by the same exponent (-0.55) for both steady-state and unsteady-state solidification conditions.