bluuebunny/crossref_metadata_2025 huggingface dataset:
Can writing facilitate the development of grammatical competence?
Authors: Polio Charlene
Published: June 2020

Although the act of writing should, theoretically, facilitate grammatical development for second
language learners even more so than speaking, most of the empirical research only indirectly supports this view, and
some research even contradicts it. In this chapter, I first discuss theoretical support for the role of writing in
grammatical development and then summarize related research with six different foci. Next, I propose studies related
to these areas, including some conceptual replications and extensions, that might help illuminate any facilitative
effects, or lack thereof, on grammatical development through writing.
The Korean hortative construction revisited
Authors: Kim Ahrim , Kwon Iksoo
Published: June 2020

This paper revisits the hortative -ca construction in Korean from a usage-based perspective,
examining its functions in natural interactional spoken data The examination of the actual occurrence of -ca
reveals its various functions: -ca indicates that the performer of the focal-event encoded in the utterance may
be 1st person plural subject, i.e., the speaker and other interlocutors; 2nd person, i.e., the addressee(s); 1st person, i.e., the
speaker; and 3rd person. Our findings provide direct evidence for the different degrees of prototypicality among these functions,
which are reflected in their different frequency counts. Furthermore, this study proposes two novel functions of
ca, the accordant imperative (to demand that the addressee agree with the speaker that the addressee perform
the focal-event) and the speaker hortative (to ask the addressee to perform an action so that the speaker him-/herself can perform
the focal-event).
Contamination and health risks assessment in a dam in the southeast region of Brazil using ecotoxicological methods
Authors: de Campos Júnior  , Araújo  , Souto  , Campos  , Pereira
Published: June 2020

Concerned with water quality, specialists have resorted to ecotoxicology as a tool to assess suspected contamination, enabling creation of strategies to repair the observed damage. Organisms such as fish and micro crustaceans are widely used in acute tests due to several characteristics
in common among them including (1) accessibility of multiple samples, and (2) enhanced sensitivity when exposed to pollutants. Thus, the objective of this investigation was to determine the degree of toxicity at different points of a dam in Coromandel, Minas Gerais, using Artemia salina
and Danio rerio as bioindicator organisms. Water was collected at three points of the dam were subsequently used to expose these organisms to different contaminant concentrations. Following exposure mortality and immobility rates were determined and compared to negative control (only
distilled water). Results with exposure of A. salina did not present significant pollution affects. However, in the case of D. rerio the mortality frequency, immobility rate and behavioral alterations was increased at point P3; thus, D. rerio demonstrated greater sensitivity
than A. salina. The physical-chemical test indicated that there were changes in parameters including biochemical demand of oxygen, dissolved oxygen and total dissolved solids (in sample at points 2 and 3), confirming toxic potential, and evidence of poor water quality at these locations.
Therefore, data demonstrated that water from the dam at certain sites is not suitable for human consumption or leisure activities such as swimming that were previously reported to occur in this reservoir by the local community.
From classical xenon fringes to hydrogen interferometry
Authors: Müller Simon R , Nedelec Patrick , Oberthaler Markus K
Published: June 2020

A setup with three equally spaced transmission gratings can be described as a moiré deflectometer in the classical regime and as a Talbot–Lau interferometer in the quantum regime. We successfully operate such a three-grating device with a de Broglie wavelength span of more than two orders of magnitude (20 fm to 2.2 pm), employing different particles such as xenon, krypton, argon, helium, and hydrogen. With that we directly observe the transition from the classical description with fast xenon atoms, to the characteristic quantum behaviour of the Talbot–Lau interferometer using hydrogen atoms with correspondingly long de Broglie wavelength. The systematic study of the interference pattern gives important insights in the feasibility of a proton or antiproton interferometer with this setup.
Feature Extraction from Turbulent Channel Flow Databases via Composite DMD Analysis
Authors: Li B. , Garicano-Mena J. , Valero E.
Published: June 2020

In this contribution we consider the Dynamic Mode Decomposition (DMD) framework as a purely data-driven tool to investigate a Reτ ≍ 950 turbulent channel database. Specifically, composite-based DMD analyses are conducted, with hybrid snapshots composed by skin friction and Reynolds stress. A small number of dynamic modes (less than 1% of the number of snapshots) is found to be able to recover accurately the DNS Reynolds stresses near the wall, with a weighted factor as an indicator for the modes selections. As a possibility of analysis large turbulent database, we conclude that composite DMD is an attractive, purely data-driven, feature extraction tool to study turbulent flows.
Coherent structures in turbulent boundary layers over an airfoil
Authors: Atzori Marco , Vinuesa Ricardo , Lozano-Durán Adrián , Schlatter Philipp
Published: June 2020

This preliminary study is concerned with the identification of three-dimensional coherent structures, defined as intense Reynolds-stress events, in the turbulent boundary layer developing over the suction side of a NACA4412 airfoil at a Reynolds number based on the chord lenght and the incoming velocity of Rec
= 200, 000. The scientific interest for such flows originates from the non-uniform adverse pressure gradient that affects the boundary-layer development. Firstly, we assess different methods to identify the turbulent-non-turbulent interface, in order to exclude the irrotational region from the analysis. Secondly, we evaluate the contribution of the considered coherent structures to the enhanced wall-normal velocity, characteristic of adverse pressure gradients. Our results show that it is necessary to limit the detection of coherent structures to the turbulent region of the domain, and that the structures reveal qualitative differences between the contributions of intense events to the wall-normal velocity in adverse-pressure-gradient and zero-pressure-gradient turbulent boundary layers.
Mapping global urban boundaries from the global artificial impervious area (GAIA) data
Authors: Li Xuecao , Gong Peng , Zhou Yuyu , Wang Jie , Bai Yuqi , Chen Bin , Hu Tengyun , Xiao Yixiong , Xu Bing , Yang Jun , Liu Xiaoping , Cai Wenjia , Huang Huabing , Wu Tinghai , Wang Xi , Lin Peng , Li Xun , Chen Jin , He Chunyang , Li Xia , Yu Le , Clinton Nicholas , Zhu Zhiliang
Published: June 2020

Urban boundaries, an essential property of cities, are widely used in many urban studies. However, extracting urban boundaries from satellite images is still a great challenge, especially at a global scale and a fine resolution. In this study, we developed an automatic delineation framework to generate a multi-temporal dataset of global urban boundaries (GUB) using 30 m global artificial impervious area (GAIA) data. First, we delineated an initial urban boundary by filling inner non-urban areas of each city. A kernel density estimation approach and cellular-automata based urban growth modeling were jointly used in this step. Second, we improved the initial urban boundaries around urban fringe areas, using a morphological approach by dilating and eroding the derived urban extent. We implemented this delineation on the Google Earth Engine platform and generated a 30 m resolution global urban boundary dataset in seven representative years (i.e. 1990, 1995, 2000, 2005, 2010, 2015, and 2018). Our extracted urban boundaries show a good agreement with results derived from nighttime light data and human interpretation, and they can well delineate the urban extent of cities when compared with high-resolution Google Earth images. The total area of 65 582 GUBs, each of which exceeds 1 km2, is 809 664 km2 in 2018. The impervious surface areas account for approximately 60% of the total. From 1990 to 2018, the proportion of impervious areas in delineated boundaries increased from 53% to 60%, suggesting a compact urban growth over the past decades. We found that the United States has the highest per capita urban area (i.e. more than 900 m2) among the top 10 most urbanized nations in 2018. This dataset provides a physical boundary of urban areas that can be used to study the impact of urbanization on food security, biodiversity, climate change, and urban health. The GUB dataset can be accessed from http://data.ess.tsinghua.edu.cn.
High potential of affordable housing supply by using industrialised building system in Selangor
Authors: Mohamed Aris N A , Fathi M S , Harun A N , Mohamed Z
Published: June 2020

The implementation of an industrialized building system (IBS) by housing developers has been a subject of argument in terms of reducing the overall costs of the housing projects which aim to sustain the supply of affordable houses to the people. To date, no real-world study has been conducted into real business cases. Thus, this case study has been carried out to verify the utilization of IBS in reducing the construction cost of housing projects. Three case studies based on interviews were reviewed and analyzed using the content analysis approach. The findings showed that there were significant differences between utilizing the IBS approach compared to the conventional method. However, the factors of volumes, IBS supplier radius, land acquisition, design, type of residential units and construction company capacity are the main concerns which have been emphasized in applying the IBS method for affordable housing supply by the developers and manufacturers. The most interesting outcome was the fast completion of the construction projects which resulted in speeding up the claiming process. Thus, the implementation of IBS will enhance the developers’ cash flow. This study concludes that the high potential of utilizing IBS components in affordable housing programs can be related to the overall reduction of construction costs, since more units were planned to be constructed in Selangor. However, the affordable housing program agencies should play a vital role in land acquisition.
A review on achieving sustainable construction waste management through application of 3R (reduction, reuse, recycling): A lifecycle approach
Authors: Mohammed M , Shafiq N , Abdallah N A W , Ayoub M , Haruna A
Published: June 2020

This study shows that there is no systematic review of research progress in literature throughout the field of sustainable construction waste management by 3R (reduction, reuse, and recycling) A lifecycle approach, The need for processes, strategies, rating systems and policies for robust and efficient waste management is widely recognized. The paper aims to evaluate. A review of sustainable construction waste management in Malaysia to maximize the 3R and reduce the disposal of construction waste by implementing a sustainable strategy throughout project lifecycle. Managing landfill shortages and long-term negative environmental economic and social effects of sustainable waste disposal are now becoming crucial for the sustainability of public health and natural ecosystems. To make adjustments, causes and factors responsible for sustainable construction waste management and progress in moving towards sustainability, it is therefore important to define the existing waste management system and causative factors adopted by industries. It allows a major shift in waste management of Malaysia by improvising current technology for waste management in a much more sustainable way. Furthermore, this ongoing research would develop sustainable construction waste procedures to sustain environmental, economic and social development for a Malaysian construction project.
BIM: The setback OR solution to project cost issues in Malaysia construction industry?
Authors: Ang P S E , Pung Y L , Tsai K L , Zulkaply M NA , Tey J S , Kasim N B , Osman M H , Musa M K , Abdul Rahman M A
Published: June 2020

Malaysia is progressing into Industry Revolution (IR) 4.0 which emphasizes more onto digital, data and artificial intelligence where everything is expected to be automated. However, cost tends to be a major issue at the pioneer stage of embracing technology where Building Information Modelling (BIM) for example tends to be a cost tussle for the current construction industry. Yet, research has shown that BIM is arguably one of the technology platforms in combating the costing issue considering that BIM enables 3D model elements to link to cost and auto-generate quantities which potentially achieve cost-effective project. Due to the conflicting perspectives of how BIM affects project cost issues, it is imperative to investigate the cost-related issues in implementing BIM in the project and to determine how BIM in general positively influences the overall project cost. Qualitative research is adopted in this study. A semi-structured interview was conducted among four professionals who employs BIM in their project. They consist of the assistant manager, senior manager and chief executive officer. The data collected is analysed by utilising Matrix Table for better organisation. The scope of the study is in the Selangor state in which the local construction industry had applied BIM in their construction industry up to the 3D stage. The results showed that the BIM implementation cost is not too burdensome as it is only a one-time cost and does not vary throughout the project period. In addition, the BIM influence on the overall cost of the project is beneficial to the industry. It improves workflow and cost management. In conclusion, BIM is beneficial to the construction industry in the long term. It is important to resolve the cost-related issues for implement BIM and hence, encourage the usage of BIM, especially in the IR 4.0 ecosystem.
Investigation on the Effect of Industrial Hygiene towards Innovation Performance: A Case of the Construction Industry in Malaysia
Authors: Zainol N Z , Jusoh M S , Amlus M A , Hamidin N , Ibrahim F A
Published: June 2020

The construction industry is growing extraordinarily, progressive and profitable. It is one of the topmost sectors that contribute to the economy of a country. Even so, it is the riskiest industry as construction workplace has the highest number of fatality and injuries. Safety and health issues remain critical to the construction industry due to its working environment and the complexity of working practices. When related to health, hygiene is one factor to be observed, in which safety is a primary concern in the construction sector. Hygiene, being part of safety and health management in site plays a significant role in the performance of an organization. At some extent, ignorance of hygiene resulted catastrophically. The present study found the influence of industry hygiene towards innovation performance in the construction industry. The industrial hygiene which measured through few dimensions, i.e. hygiene knowledge, personal hygiene behaviour and hygiene personnel protection equipment are tested against innovation performance as the dependent variable. Following the comprehensive reviews, it is pertinent for the research to choose a quantitative undertaking, where questionnaires survey is the primary tool to collect the data among the construction companies, i.e., developers and contractors that registered with CIDB. The instrument will be developed to investigate the influence of industrial hygiene practices toward innovation performance. The research objectives will be achieved by statistically analyzing the collected data with Structural Equation Modeling (SEM) to verify the relationship between the variables.
Compressive strength and workability of high calcium one-part alkali activated mortars using response surface methodology
Authors: Haruna S , Mohammed B S , Wahab M M A , Haruna A
Published: June 2020

In this present experimental study, high calcium fly ash was utilized in the production of one-part alkali activated mortars. The HCFA was activated with anhydrous sodium metasilicate powder at 10 – 20 percent of the total precursor materials and cured at ambient condition. In this study, granular anhydrous sodium metasilicate has been successfully utilized to produce one-part alkali activated mortars. Thirteen mixes of one-part geopolymer mortar were designed using RSM central composite design with percentage of alkali activator and w/b ratios as parameters. Hardened density, workability, and, compressive strength was envisaged. The results showed that increasing the granular activator beyond 15% by weight of the fly ash reduces the strength and workability of the one-part alkali activated mortars. The RSM investigation helped in advancing the level of granular activator as far as acquiring ideal qualities and they were observed to be ideal at 16% of the granular activator and 0.3 w/b proportion. The model conditions were created, and the outcomes were approved through ANOVA by witnessing the model noteworthiness level of more than 95%. One-part alkali activated mortars exhibited highest compressive strength of almost 40 MPa at 28 days curing. The density of the one-part geopolymer mortars is almost the same regardless of the mixes.
A review on oil and gas pipelines corrosion growth rate modelling incorporating artificial intelligence approach
Authors: Nasser A M M , Montasir O A , Wan Abdullah Zawawi N A , Alsubal Shamsan
Published: June 2020

One of the necessities of an effective oil and gas pipeline safety Management Plan (SMP) is the establishment of safe and efficient risk assessment strategy for pipelines where the significant danger is corrosion. Corrosion growth is related to several factors involving pipe material, pipe condition, and defect geometrical imperfection. Thus, the assurance of a proper corrosion assessment requires the prediction and evaluation of corrosion growth rates. The prediction of corrosion growth rate precisely, would minimize the cost of pipelines maintenance through the determination of the deteriorated pipeline segments. In line inspection (ILI) has been used to detect the pipelines corrosion, also the corrosion can be detected by other inspection tools such as Magnetic flux leakage (MFL) and Ultrasonic tool (UT). However, there are numerous models have been utilized to anticipate the corrosion growth rate such as deterministic and probabilistic models. Recently, there are conducted researches on the application of artificial intelligence in predicting corrosion growth rate for oil and gas pipelines such as artificial neural network (ANN) and fuzzy logic (FL). This paper aims to provide a comprehensive comparison between the conventional methods, i.e. deterministic and probabilistic and artificial intelligence methods, i.e. Artificial neural network (ANN) and fuzzy logic (FL) in the prediction of corrosion growth rate of oil and gas pipelines. This review would be helpful to pipelines operators to understand the effectiveness of artificial intelligence approach compared to conventional methods in corrosion growth rate modelling.
The effect of coal bottom ash in mechanical and environmental performances for polymer composite
Authors: Zainal F , Kamal F , Yusop H , Diana R , Zakaria S
Published: June 2020

Fabrication is essentially the manipulation of raw materials into a desired product based on a workable approach. In this project, fabrication is fundamentally the process by which coal bottom ash (BA) are compatible with resin to form and improve construction materials which satisfy the assigned requirements and applications. BA have a porous and granular structure which limits its application and commercialization. Many investigations have been carried out towards the effective utilization of other reinforcement material or fillers such as fly ash for both concrete composite and polymeric composites. From this research project, resin was used as binder materials to BA which have porous and granular structure that limits its application. Despite of that, the resin can be transformed and tailored to fit specific needs. The findings show resin was greatly cooperated more than 40% of BA in the mixture which directly improve the mechanical performances on drop impact test. A part from that, environmental issues should be considered in utilizing BA. Since the BA is classified under scheduled waste (SW 104) which contains heavy metals, CBA blended with resin were readily in encapsulation form to mitigate the leaching of metals towards surrounding. Leachate study was conducted to all sample compositions and there is no leaching of metals detected from the sample due to increase in chemical stability. The concentration of toxic metals that leached were below than threshold value set by Department of Environment, Malaysia (DoE).
Properties of cement mortar containing NaOH-treated Crumb rubber as fine aggregate replacement
Authors: Tudin D Z A , Rizalman A N
Published: June 2020

In this study, crumb rubber was used to partially replaced fine aggregate in mortar mixture by 5, 10, 15, and 20 volume percentage (vol%) with untreated and NaOH-treated crumb rubber. Thus, the total number of mixtures was 9. The mortars were tested for its flowability, compressive strength, flexural strength and density. Based on the results, increasing the replacement percentage of fine aggregate by crumb rubber reduced the compressive strength, flexural strength and density of rubberized mortar but increased the flowability. Meanwhile, the treatment of crumb rubber using NaOH solution improved the flowability, compressive strength and flexural strength. The treatment has minor effect on the hardened density of the rubberized mortar.
Carbonation and strength of self-compacting concrete with coal bottom ash exposed to seawater by wetting-drying cycle
Authors: Hamzah A F , Wan Ibrahim M H , Manan E A
Published: June 2020

This experimental work presents the carbonation and strength behaviour of self-compacting concrete with coal bottom ash that was exposed to cyclic wetting-drying processes under condition of seawater environment. Six series of mix portions with 0%, 10%, 15%, 20%, 25% and 30% of coal bottom ash replacement to sand were produced. The samples arising from each mixture were exposed to seawater environment with an average of 15 hours of wetting and 9 hours of drying process per day. Thus, the carbonation and compressive strength behaviour at the durations of 28, 60, 90 and 180 days under curing process were observed. The results obtained in this study for seawater exposure has clearly indicated that the incorporation of 10% replacement of coal bottom ash to sand exhibited good result of carbonation and compressive strength.
Degradation of limestone exposed to drying and wetting cycles – experimental study
Authors: Al-Bared A M , Harahap I S H , Azuddin N H , Marto A , Alavi Nezhad Khalil Abad S V , Ali M O A , Isah B W
Published: June 2020

Degradation of rock is the deterioration of the rock forming materials and the reduction of strength and stiffness within time. It is responsible for the failure of rock slopes and landslides as the drying and wetting cycles in long-term will extensively reduce the strength of the rock and eventually end up as a soil-like material. Weathering rate is very crucial, and it is the main parameter inducing and accelerating degradation of rock. This study focuses on investigating and evaluating the effect of degradation on cored samples of limestone. Limestone was collected from the state of Perak, Malaysia and the samples were cored, trimmed and cut into 50 mm diameter and 80 mm height. A total number of 30 samples were exposed to different number of drying and wetting cycles in the laboratory. A total number of 27samples were tested using the Uniaxial compression test after 0 – 14 cycles while three samples were exposed to exactly 14 cycles to observe the reduction in weight. The results showed the strength of limestone to decrease gradually with the increment of drying and wetting cycles. Besides, samples that were continuously exposed to 14 drying and wetting cycles experienced a weight reduction of approximately 1.12%.
Effect of natural fibers on the soil compaction characteristics
Authors: Bawadi N F , Ahmad N S , Mansor A F , Anuar S A , Rahim M A
Published: June 2020

Clay soils are considered as a problematic soil in term of water absorption rate. The ideas of soil improvement method had been widely used to modify the physical and mechanical properties of clay soil. This study aims to identify the optimum percentage mixing of natural fibers in influencing the compaction characteristics. X – ray fluorescent test (X-RF) and Standard Proctor test has been performed to determine the chemical composition of natural fibers and compaction characteristics of soil samples. Natural fibers such as banana, kenaf, and coconut coir were used as a natural soil stabilizer with varying percentage mixing to increase the properties and stability of soil samples. Experimental data obtained from compaction test shows that the appropriate maximum dry density and optimum moisture content for each natural fiber are at 0.5% natural fibers mixing. In this study, the maximum dry density and optimum moisture content for untreated samples are 1650kg/m3
and 7.8%, respectively. Meanwhile, for treated soil samples that mixed with banana, coconut and kenaf fibers are 1760kg/m3
, 1780kg/m3
, 1670kg/m3
and 8.2%, 8%, 11%, respectively. Hence, 0.5% mixing with banana fibers indicated the best possible amount of dry density and moisture content among other natural fibers. Therefore, this study proved that natural fibers can act as a good natural soil stabilizer in increasing stability of clay soil.
Analysis of thermal power plant fly ash and lime in increasing shear strength of soft clay
Authors: Mohamed S F W , Yahya S
Published: June 2020

Soil is the basic foundation for any civil engineering structures. It is required to bear the loads without failure. In some places, soils are weak which cannot resist the oncoming loads. Soft clay is known to have low strength and high compressibility. Utilization of additive is a method that can be applied to increase shear strength of soft clay. This study was conducted to determine the effectiveness of mixing fly ash, lime and soft clay with different percentage in order to increase the strength. A series of laboratory test were conducted in determining the physical properties, compaction and shear strength on soft clay soil. The soil samples; both disturbed and undisturbed were obtained from the vicinity of Politeknik Sultan Idris Shah (PSIS). Two tests carried out are compaction and direct shear strength. From the results, the highest strength of soft clay was at 69 kPa by mixing soil with 12% fly ash + 4% lime.
Laboratory investigation of suction distribution in a modified capillary barrier system
Authors: Yunusa G H , Kassim A , Umar M , Talib Z A , Abdulfatah A Y
Published: June 2020

This paper investigated the effect of transport layer in the diversion capacity of natural capillary barrier system using laboratory slope model. The slope model was constructed with stainless steel and 5 mm thick acrylic sheets. Grade VI and grade V soils classified as sandy silt of very high plasticity (MVS) and silty gravel of high plasticity (MHG), respectively were arranged in the slope model with sand and gravel transport layers sandwiched at their interface. The model was subjected to different rainfall intensities using rainfall simulator to determine the behaviour of water flow and suction distribution in the slope model. The results obtained show a modification in the suction distribution behaviour and the natural capillary barrier effect was sustained. It was also observed that a transport layer formed with gravel material was more effective in diverting the infiltrating water compared to that of gravelly sand. This occurred because the upper grade VI layer possessed capillary forces due to its finer pore structures and relatively large air entry value, thus, it retained the infiltrating water, and the gravel transport layer possessed relatively larger pore structures compared to the grade VI layer and hence it possessed higher hydraulic conductivity values and small water entry value. This arrangement, provide a capillary break and allowed the infiltrating water to flow above the interface. Therefore, the inclusion of transport layer provides a definite path through which the infiltrating water flows and diverted laterally. Thus, improving the performance of natural capillary barrier effect.
Numerical simulation and full-scale field testing of steel parapet railing under impact of heavy truck loads – comparative study
Authors: Che Osmi S K , Rosdi A , Husen H , Sojipto S , Misnon N A , Khairuddin F H
Published: June 2020

Bridge parapet is one the most critical part of the bridge superstructure, which functions as a safety feature during accident or collision at the edges of the bridge. For steel parapet railing, complete full-scale field testing needs to be carried out before installation of new parapet railing. Field testing not only expensive but also very time-consuming for preparation and testing works. In this study, a comparison between the results of an actual field test and numerical simulation works was investigated. The chosen 3S two-beam steel parapet had passed the field testing conducted by the Korean Transportation Safety Agency (KOTSA). For comparison, the performance of the steel parapet selected railing was simulated under impact loading of heavy trucks, whereby no passenger car test was conducted. The parapet railing design was modelled and simulated using the SolidWorks and the NASTRAN/PATRAN software, respectively. Five case studies were derived to ensure the reliability and accuracy of the obtained results. Case 3 recorded the lowest difference percentage of 3.6% for the maximum deformation of the parapet railing. However, other case study recorded more than 10% discrepancy of the maximum deformation (i.e. Case 1, 2, 4 and 5). It can be concluded that Case 3 as the right position where the impact load exerted during the field testing. These results proved that the numerical simulation results provide a reliable result for testing the quality of the parapet railing with a minimum cost and time required, consequently, tackle the shortcomings of the field testing.
Investigation of prestressed concrete sleeper’s vibration located at KM71.75 And KM79
Authors: Rozli M I F , Hilmi Safiuddin C M C J M , Kay Dora A G , Senin S F , Rahman A S A , Ali M R M , Amin N M , Nordin M N F
Published: June 2020

Train has been one of the essential and convenient transportation choices for community nowadays. Instead of carrying a passenger, these types of facilities also can be used to transport material across our country. With the increasing usage of train every year, the rate of accidents has also increased dramatically. Therefore, the importance of studying about the railway can contribute to building better and comfort railway track which can deliver their services at its best for an extended period. This study focused on the measurement of the deflection of concrete sleepers which affect the performance of the railway track. Lack of actual deflection value from the site can be problematic to ensure the quality of the track itself. The method used for the analysis is by using the Sirius-M instrument which can be recorded and analyses the acceleration of the concrete sleepers when receiving the loading wave from a moving train. The data of acceleration then can be transformed into deflection form by applying double integration. From the data collection, it shows that the maximum deflection at northbound at KM79 is 13.72 mm for freight train and 1.5 mm at southbound for six set commuter train. As for KM 71.75, the maximum deflection at northbound is 0.57mm for ETS and 1.5mm at southbound for six set commuter train. Thus, from this research, the actual deflection value from both sites were achieved.
Design and optimization of polyurethane modified bitumen (PUMB) using response surface method
Authors: Khairuddin F H , Yusoff N I Md , Badri K , Koting S , Choy P N , Misnon N A , Che Osmi S K
Published: June 2020

This paper discusses the utilization of Response Surface Method (RSM) statistical tool to determine the optimal amount of polyurethane (PU) for modifying 80/100 penetration grade bitumen. Central composite design (CCD) was used to develop an experimental design matrix where bitumen and PU are designated as the factors while penetration, softening point and viscosity are designated as the response. Numerical analysis of polyurethane modified bitumen (PUMB) shows that the optimal amount of PU in the modification of the bitumen is 5%. Verification of the chosen model shows that it is in consistent with the experimental value since the percentage error is less than 5%. Result of the consistency test shows that the addition of 5% PU resulted in higher penetration and viscosity values but lower softening point value, which in consequent improve bonding strength as the flow of bitumen is reduced.
Study on pervious concrete pavement mix designs
Authors: Ahmed T , Hoque S
Published: June 2020

Increased precipitation in recent years due to the effect of climate change is leading to increased surface runoff and water logging in urban areas while impervious concrete or asphalt covering of urban lands hinders groundwater recharge. However, Pervious Concrete Pavements have the capacity of functioning as a Sustainable Urban Drainage System (SUDS) by allowing surface water to infiltrate downwards through the porous structure of the pavements, thereby minimizing flooding risks, recharging ground water, reducing run off and peak flows, alleviating the precipitation load on overstressed drainage systems, and improving water quality by capturing pollutants. This research provides an overview on pervious concrete mix designs and their effect on strength and permeability. Materials of pervious concrete include those used in conventional concrete, however eliminating the fine aggregate content. Different mix designs have been prepared and tested to understand the behavior of Pervious Concrete and recommend an ideal mix. The findings from the Compressive Strength Test and Standard Test Method for Infiltration Rate of in place Pervious Concrete, investigate the gradually varying properties of pervious concrete with changes in the mix which are reported and discussed. Results indicate that a fine balance between compressive strength and permeability is not possible however pervious concrete pavements can be an acceptable alternative when used in low volume and low impact areas.
Assessment of level of service (LOS) for entrance ramp merging by using HCM US 2000 and HCM US 2010
Authors: Bakhari N S , Adnan M A , Tuan Badrol Hisham T B
Published: June 2020

Congestion is a normal occurrence on the urban Malaysian expressway system, usually associated with areas having entrance ramp, exit ramp and weaving section. A good practice for expressway system can be determined by the efficiency of the traffic operation itself. Thus, this research paper provides the assessment of level of service for entrance ramp merging using US HCM 2000; US HCM 2010 and empirical data as the indicator. Study was conducted at KM 12, Grand Sepadu Expressway, Selangor and the data were collected by using TRAX Apollyon Automatic Traffic Counter. An analysis was conducted and the RSME result shows that the plotted data are successfully developed and validated in these studies.
Carbonization effect on EFB briquettes prepared with different type of binders
Authors: Nazari M M , Idroas M Y , Ayuni F A
Published: June 2020

Biomass energy is gaining public interest as a result of the environmental impacts and depletion of fossil fuel resources. Thus, biomass briquettes have emerged as an attractive option due to its huge renewable energy potential. The biomass briquettes are used for thermal applications because it can produce complete combustion as it has consistent quality and high burning efficiency. However, the quality of the briquettes can be added by application of carbonization treatment method. Carbonization of biomass is a waste treatment process in which a biomass is heated in an oxygen-free or oxygen-limited environment. In this study, carbonized EFB was blended with binders and densified into briquettes. The mixing ratio of binders to carbonize EFB were fixed at 20%. The effect of the carbonization treatment on the briquette properties and combustion characteristics was studied through proximate and ultimate analysis while high heating value (HHV) was analyses by using bomb calorimeter. To explore the potential of carbonized EFB briquettes, the results were compared to untreated EFB briquettes. Results indicate briquette TS2 as the optimum formulation since it owned moderate physicochemical properties. In addition, the briquette had highest HHV of 23.62 MJ/kg which is approximately 30% higher than briquette prepared from untreated EFB. Overall, carbonized EFB blended with tapioca starch was found to improve the briquette quality and enhance the possibility to use as syngas production.
Torrefaction of palm kernel shell using conventional and microwave irradiation pretreatment
Authors: Ahmad R , Ishak M A M , Kasim N N , Ismail K
Published: June 2020

This study describes the properties of torrefied palm kernel shell (PKS) by conventional and microwave irradiation (MI) pretreatment. In conventional pretreatment, the untreated PKS was torrefied using fixed bed reactor at temperature of 210, 230, 250, 270 and 290 °C for 60 min of holding time. In MI pretreatment, the untreated PKS was irradiated with microwave power of 200, 300, 450 and 600 W for 8 min of holding time. The torrefied samples were analysed for mass and energy yield, energy density, calorific value and proximate and ultimate analysis. The results showed that, the properties of torrefied samples were improved with increasing torrefaction temperature and microwave power. The mass and energy yield, moisture, volatile matter and oxygen content of torrefied PKS decreased, whereas, the calorific value, energy density and carbon content increased with increasing torrefaction temperature and microwave power. The torrefaction temperature of 270 °C and microwave power of 450 W were appropriate to upgrade the PKS properties. Therefore, the change in properties of torrefied PKS revealed the potential of applying pretreatment prior to further thermal conversion such as pyrolysis and gasification.
Microwave-assisted in situ transesterification of wet microalgae for the production of biodiesel: progress review
Authors: Fazril I , Shamsuddin A H , Nomanbhay S , Kusomo F , Hanif M , Ahmad Zamri M F M , Akhiar A , Ismail M F
Published: June 2020

Continuous efforts are done by scientists in the quest of finding sustainable alternatives for fossil fuels. Various feedstock have been carefully selected to be utilized in the production of biodiesel. Microalgae has garnered a lot of attention as early as in the 80s and is regarded as one of the most promising feedstock to displace fossil fuel. However, the utilization of microalgae as feedstock in a mass production of biodiesel comes with considerable challenges. One of the main obstacles is the high cost involved in processes such as drying and the subsequent lipid extraction of the biomass. These two energy extensive processes created a bottleneck in the biodiesel production at a large scale. As a remedy, direct or in situ transesterification of the wet microalgae biomass can be applied to entirely circumvent the two processes; hence substantially reducing the production cost. However, the presence of water in the wet microalgae biomass posed a challenge in the transesterification process. This paper covers the specific techniques of utilizing microwave irradiation during the in situ transesterification of wet microalgae biomass.
Properties and environmental impact of available firewood in Brunei Darussalam
Authors: Yazdani M G , Ligoh N. , Ali M.H.
Published: June 2020

Five types of firewood used in Brunei Darussalam is identified. Properties, such as wood density, moisture percentage, ash content and elemental composition of plants were determined and correlated with the calorific value and evaluated in relation to their properties and environmental impact when burned. It was revealed that the firewood with the highest calorific value does not necessarily constitute the best option as fuel, if elemental composition is taken into account. The variation of the wood density, calorific value, ash contains and elemental composition C, N, and their indirect impact on the environment are discussed in this paper.
Effect of operating parameter on the anaerobic digestion oil palm mesocarp fibre with cattle manure for biogas production
Authors: Saidu M , Yuzir A , Salim M R , Richard A , Afiz B
Published: June 2020

Anaerobic digestion is a complex biological process resulting in the conversion of biodegradable organic matter into biogas and mineralized material. Anaerobic digestion involves the breakdown of biomass by a concerted action of a wide range of microorganisms in the absence of oxygen. The biological pre-treatment was used to reduce the lignocellulose content of substrate. Laboratory experiment was carried out in single stage 10 L bioreactors. The reactors were named R1, to R10 at different mixture conditions with organic loading of 1.62 and 2.11 g VS at HRT of 10 days. The result was stable at the initial stage, within the first 10 days was high and was attributed to the consumption of easily degradable COD. These indicate that there is stable COD removal efficiency for the anaerobic digestion of treated OPMF with CM and seeded with POME. The results showed the level of COD removal efficiency was observed and upon the steady state of the reaction. In this experiment, the results indicate that chemical oxygen demand (COD) reduction in reactor R1 shows the best result of the average removal efficiency value of 37.9 %. Although, ambient temperature was adopted, it still shows a high COD removal efficiency in R1 and may be associated to a more stable reaction. This indicated that pre-treated OPMF produced a better COD removal efficiency than the untreated OPMF. The removal efficiency started with 18 % and continued to increase to 38 %. The removal efficiency became relative stable until day 30 which give the highest percentage removal of 45 % which was achieved with a high OLR (2.11 kg VS L−1 d−1). The reductions continued in the same trend until day 20 and remained stable till the end of the experiment. This indicates that the available microorganisms have been exulted by day 20 and this corresponds to a drop to the rate of biogas production. Operating parameters considered in this study have an influence on the rate of biogas produced during anaerobic digestion. The results show that COD, do influence the rate of biogas production.
Interlocking compressed earth bricks as low carbon footprint building material
Authors: Asman N S A , Bolong N , Mirasa A K , Asrah H , Saad I
Published: June 2020

The building construction significantly contributes to the carbon growth due to the high carbon emissions produced by buildings and their effects on climate change. Malaysia has devoted to reduce the carbon dioxide emission by the year of 2020. Therefore, the Interlocking Compressed Earth Bricks (ICEB) has been introduced as an alternative for low carbon building material. This paper studies the carbon footprint of Interlocking Compressed Earth Bricks as a walling structure in buildings or residential houses. The Interlocking Compressed Earth Bricks system is an improvement from the conventional brick production where the brick is fabricated by compressed method (not fired), thus reducing the carbon emissions. This paper presents a cradle-to-gate carbon emission study of a multi-story residential building in a Community house in Tawau, Sabah by using the life cycle assessment (LCA) methodology. The total carbon of the buildings using conventional FCB and ICEB construction are 405.75 kgCO2/m2 and 264.50 kgCO2/m2, respectively, which are comparable with the results of similar studies found in the literature. In order to achieve low-carbon buildings for the residential houses in Sabah, the use of ICEB as alternative materials with low carbon intensities and sustainable construction practices are suitable and recommended. The result shows that the implementation of Interlocking Compressed Earth Bricks contributes to carbon footprint reduction of 35% from the conventional and suitable to be used as a low carbon footprint building material.
Citrus aurantiifolia and citrus microcarpa fruit peels waste as eco-friendly natural coagulants
Authors: Dollah Z , Sahat N A , Hamzah N , Musir A A , Ramli R
Published: June 2020

Turbidity is one of the importance of physical water quality parameter in the water treatment process. Aluminum sulfate (alum) and ferric chloride are the most widely groups of chemical coagulant and have been extensively used to remove turbidity. However, there are several flaws relates to the environmental issue and impose health risk to the consumer. Fruit peel waste as a natural coagulant is one of the alternative techniques in minimizing the usage of chemical coagulant in water treatment. This research focused on a combination of ratio 60:40 and 80:20 of citrus microcarpa peels and citrus aurantiifolia peels to act as a natural coagulant for turbidity removal. Furthermore, the effect of mixing duration is determined to establish the optimum mixing duration for the highest turbidity removal. Standard practice using jar test were performed in synthetic turbid water using kaolin. The highest turbidity removal occurred at optimum ratio of 80:20 with 77.6% efficiency removal where the optimum mixing duration was found to be at 120 rpm of rapid mixing at 3 minutes, 50 rpm of slow mixing at 20 minutes and 60 minutes of settling time. The study demonstrated that combination of citrus aurantiifolia peels and citrus microcarpa peels have the potential to be used as natural coagulant for a future alternative in water treatment.
Recovery of nano-lignin from anaerobic treated palm oil mill effluent (AT-POME)
Authors: Ismail H S , Ibrahim A H , Abidin C Z A , Ridwan F M
Published: June 2020

Lignin is the main polymers in woody biomass aside cellulose and hemicelluloses Recently, nano-lignin is gaining importance due to the increasing demand for bio-based and bio-active nanomaterial fillers for many applications such as in composite and textile industries. Palm oil mill effluent (POME) is the main wastewater produce by palm oil mills. Anaerobically treated (AT-POME) contains high soluble lignin due to the anaerobic digestion of cellulosic material in POME. Nano-lignin was precipitated by adjusting the initial pH of AT-POME during the sonication process. Sulfuric acid (H2SO4), nitric acid (HNO3), hydrochloric acid (HCl) and phosphoric acid (H3PO4) were used to adjust the initial pH of AT-POME. Result shows that sulfuric acid was the most suitable acid to be used as it could recovered 96% of the soluble lignin in AT-POME. The presence of ultrasonic during the precipitation process had reduced the size to 383.4 nm. The optimum operating parameter for lignin recovery is at pH 4 using sulfuric acid and sonicated at 80 watts for 15 minutes. This study shows that sonication could reduce the size of precipitated lignin from AT-POME. In addition, removal of lignin from AT-POME also reduced the COD content of AT-POME.