bluuebunny/crossref_metadata_2025 huggingface dataset:
Developing a conceptual framework of building maintenance driving factors for effective heritage building maintenance programme in Malaysia
Authors: Syed Mohamad S B H , Rahman M A A , Suratkon A , Deraman R , Zakaria M N
Published: June 2024

The purpose of this research concept paper is to explain the initial development process of a proposed conceptual framework of building maintenance driving factors for an effective heritage building maintenance programme. The maintenance programme is the most important phase in arranging the building maintenance management process. The heritage building value always will decrease within a period of time. If the relevant maintenance procedure fails to detect the root causes of building deterioration, it will have a significant impact on the durability and strength of heritage buildings. This research is initiated in order to search further on the significant effective maintenance driving factors. The maintenance driving factors will be the indicators in filling the gap for improving the heritage building maintenance programme and comprehensive heritage maintenance framework. The aim of this research is to develop a comprehensive framework that depict the significant driving factors of the effective building maintenance programme for a heritage building in Malaysia. The research objectives are to investigate the significant driving factors which are involved in the maintenance programme and to examine the significant connection between the driving factors in developing an effective maintenance programme for heritage buildings in Malaysia. The relevant research data collection has been obtained by conducting expert opinion interviews and findings from literature reviews. Several factors have been identified as the enablers of the effective heritage building maintenance programme, and clustered into 4 main factors (Human Factor; Management Factor; Organisational Factor, and Technology Factor). In conclusion, the research will be able to give significant findings regarding the driving factors involved in the development of a conceptual framework for an effective heritage building maintenance programme.
A Review on Dominant Factors of Project Manager Competency in Various Implementations for the Construction Industry
Authors: Rustam Adriadi , Yasin Mohd Norazam , Zainuddin Mairizal , Yusoff Khairul Nizam , Kamil Nurul Atiqah
Published: June 2024

In carrying out construction projects, the competence of a project manager is always debated by civil engineering practitioners, because the project manager is very important and a key factor in achieving successful project implementation. Therefore, a project manager must have the appropriate competencies to lead the implementation of construction projects. Existing competency research has been identified from various global competency sources, such as IPMA Competency Base Line (ICB), APM Competency Framework (ACF), and Project Management Competency Development (PMCD). When looking at it as a whole, their competencies have a lot in common with the competencies in PMCD. There are three main groups of PMCD competencies namely: Knowledge Competence, Technical Competence, and Personal Competence. This research examines previous research articles related to project manager competencies for successful projects. This research was randomized to global research since 5 years ago, starting from 2018 to 2022. This paper reviews the competencies strictly to determine the dominant project manager competencies that are widely used in the implementation of construction projects. This research examines and determines the appropriate factors sequentially in the three competency groups for project success. This study produces the most dominant competency factors and is widely used by project managers to be successful in handling construction projects.
Instrumented pile load tests in limestones and granite formations - case studies with optical fibre strain sensors
Authors: Mohamad H , Beddelee A A A M , Tee B P
Published: June 2024

In instrumented pile load tests, obtaining a reliable strain profile is crucial to interpret the load-transfer behaviour of the test pile. For conventional instrumented pile load tests, an extensive quantity of point-based sensors such as vibrating wire strain gauges and tell-tale extensometers were installed to measure strains and pile deformation especially when the test pile is long and with large variation in soil stratum. The advancement of distributed fibre optic sensor (DFOS) technology, has significantly improved the conventional instrumented pile load test method. DOFS based on Brillion Optical Time Domain Analysis (BOTDA) is a novel technique for measuring strains in a continuous manner that outweighs the conventional point-based sensors. A full continuous pile length strain profile minimised misinterpretation of the load-transfer and mobilised shaft friction of the test pile, especially the cast-in-situ pile. This paper discusses two case studies of instrumented pile load tests performed using BOTDA technology for the Klang Valley Mass Rapid Transport (KVMRT) project found in limestones and granite formations. The interpreted results in terms of load transfer response, average unit shaft resistance, and elastic shortening of rock socketing piles are in exceptional agreement with conventional instrumentations such as Vibrating Wire Strain Gauges (VWSG) and Linear Variable Displacement Transducers (LVDT) at 6% difference. The maximum unit shaft friction acquired in the granitic layer was about 2,200 to 2,500 kN/m2 whereas the pile founded in limestones achieved maximum unit shaft friction of 1,800 to 1,900 kN/m2.
Campus walkability: enhancing pedestrian safety through installation of raised crosswalks
Authors: Mohd Noor Azmi A E , Daniel B D
Published: June 2024

Walking is one of the most common sustainable modes of transportation in university campuses. To ensure its sustainability, pedestrian facilities that are safe, comfortable and reliable must be adequately provided. Various traffic calming measures have been introduced to enhance the safety of pedestrians. In Universiti Tun Hussein Onn Malaysia (UTHM), 6 raised crosswalks (RCW) have been installed along Persiaran Tun Ghafar Baba. This study aimed to investigate the impact of RCWs on vehicular speed reduction. Speed data were collected at each RCW. Vehicle speeds were recorded before, at and after the RCWs. Speed profiles developed indicate that the 85th percentile speed difference of RCWs were 14 – 25 km/h, which meant that the percentage of speed reduction at RCWs were remarkably high (31 – 48% reduction). Statistical tests confirmed that all RCWs yielded significant drops in speed i.e., the peak mean travelling speed versus the operational speed at the device. Furthermore, it was found that the zones of influence were between 29 – 50 m. This shows that drivers start reducing their speeds from as far as 50 m from the RCWs. Based on these findings, it can be concluded that raised crosswalks are effective in reducing speed, thus enhancing pedestrian safety while crossing as drivers tend to be more aware of their surroundings at lower speeds.
Geobamtile to Support Road Embankment Over Deep Soft Ground
Authors: Mokhtar N , Low K S
Published: June 2024

Road surface profile failure is often a major issue for roads. This paper presents a way of providing support beneath the road embankment between the over-deep soft ground which is referred to as “Geobamtile.” It is designed and constructed to prevent failure due to the type of subsoil that accommodates the entire structure of the road itself. The construction of roads, whether new roads or upgrading existing roadways is bound to the alignment and might be allocated on problematic land that needs appropriate treatment before any structures can be built. A way of providing geobamtile is being studied and developed in Malaysia and has made it possible to safely build road embankments over extremely soft and deep sub grades areas without creating significant post-construction settlements. These useful advantages are made possible by the extraordinary tensile and bending capabilities of bamboo in bundles. The area and amount of buoyancy characteristic can be easily adjusted by the number of tiers of bamboo-geotextile set-up within the system during construction. The expected supporting load and amount of post-construction settlement can invariably be manipulated to some extent. In general, this green and sustainable invention design will have a positive social impact by providing significant financial benefits to rural and indigenous populations.
Assessment of permanent deformation on asphalt mixtures incorporating Forta-Fi fibre as additive material
Authors: Aman M Y , Musa N F A A , Bujang H , Shahadan Z , Taher M N M , Rohani M D , Danial D B , Arumugam T N
Published: June 2024

An increasing number of load applications has caused permanent deformation that leading to longitudinal depressions in the wheel paths and small upheavals at the sides and subsequently effects the ride quality for road users. To address this issue, modifying asphalt mixtures using Forta-Fi fibre was introduced. This paper focuses to assess the permanent deformation and resistance to rutting of the asphalt mixtures containing Forta-Fi fibre. In this study, the influence of Forta-Fi fibre on asphalt mixtures was investigated by incorporating four different percentages of the fiber (0%, 0.3%, 0.5%, and 0.7%). The asphalt mixtures were prepared using a conventional bitumen 60/70 penetration grade as the base binder. Compacted specimens were subjected to dynamic creep testing with deviator stress levels of 207 kPa and 500 kPa, performed over 3600 cycles at a 60°C. The findings demonstrate that the inclusion of 0.3% Forta-Fi fiber in asphalt mixtures tested under deviator stress loads of 207 kPa and 500 kPa increased the creep stiffness by 26.1% and 43.1%, while the permanent deformation decreased by 18.4% and 43.8% compared to specimens without the Forta-Fi fibre. Additionally, the rutting values showed a reduction of 12.2% and 24.3% in the respective stress conditions. In contrast, an excessive percentage of Forta-Fi fibre was added, the creep stiffness exhibit reduce as increases permanent deformation and potential to rutting. This outcome is attributed to the impact of fibre components on the elastic behavior of the mixtures. In conclusion, the inclusion of 0.3% Forta-Fi fibre in the specimens resulted in improved resistance to rutting and overall better performance compared to conventional mixtures.
Carbon monoxide emission and eco-driving for freight sustainability
Authors: Ruslan H
Published: June 2024

Carbon monoxide (CO) indirectly causes climate change because it affects the abundance of greenhouse gases such as carbon dioxide and methane. Carbon monoxide is formed because of incomplete combustion in diesel engines. The fate of CO towards achieving freight transportation sustainability is presented. Firstly, the pollutant (CO) emitted by diesel engines from freight vehicles was determined from field studies using the tailpipe emission technique. The effect of the behavioural approach, eco-driving, was also observed for the 304 km trip demonstrated by the drivers of the 40-footer truck. Eco-driving has many advantages, including emitting less CO, saving in fuels, and reducing accidents and traffic summons. Secondly, for freight sustainability, CO should be further reduced by adhering to Euro standards of the European Union for heavy-duty vehicles, which states that the emission should be 1.5 g/kWh. Thirdly, a diesel oxidation catalyst (DOC), which converts CO to CO2, is an option that can be used. Then fourthly, the decarbonisation of transport using heavy electric trucks also shows some promise, although they are best for moving goods for a short distance. Finally, an efficient logistics system with optimal solutions adopting several measures is suggested for sustainability. These include ‘Hub-Spokes’ distribution, a polarised fleet, expanded delivery windows and last-mile delivery. Thus, these five steps help decarbonise the transport sector and consequently accelerate the zero carbon emission transition.
Chemical characterization of asphalt binder containing palm oil mill sludge
Authors: Norazni N S A , Kamaruddin N H M , Yunus K N M , Poharan A , Azahar W N A W
Published: June 2024

Modification of asphalt binder is continuously explored due to its escalating cost and increasing demand for this non-renewable material. As an alternative, the potential of waste materials was assessed for use as a modifier in asphalt binder. This study focuses on investigating the physical properties of unmodified and modified asphalt binders, with a specific emphasis on the chemical properties of palm oil mill sludge (POMS) modified asphalt binder. In this investigation, the control sample employed was PEN 60/70, while the POMS content ranged from 0% to 5% with an increment of 1%. Penetration and softening point tests were conducted on the POMS-modified binder, and Fourier Transform Infrared Spectroscopy (FTIR) tests were conducted to assess the chemical properties of both un-aged and short-term aged asphalt binders. The results revealed that the addition of POMS modified the asphalt binder by inducing a softening effect proportional to the percentage of POMS. The aging process was found to be significantly delayed in the POMS-modified binder with increasing POMS content.
The effect of aggregate micro and macro texture on pavement skid resistance of Malaysia road network
Authors: Taher M N M , Aman M Y , Bujang H
Published: June 2024

The skid resistance of the surface of the highway is controlled by its microtexture and macrotexture. Microtexture refers to irregularities in the surfaces of the stone particles (fine-scale texture) that affect adhesion and make the stone particles feel smooth or rough to the touch. Macrotexture refers to the larger irregularities in the road surface (coarse-scale texture) that effect hysteresis and associated with voids between stone particles. This paper evaluates the effect of aggregate microtexture, macrotexture and influence of pavement surface under dry and wet condition to skid resistance. Three (3) different types of pavement surface were selected to obtain friction value on Continuously Reinforced Concrete Pavement (CRCP), Hot Mixture Asphalt pavement (HMA), and Ralumac Micro-Asphalt. In addition, skid resistance value was calculated from British Pendulum Tester and texture depth by using sand patch method. From the field test conducted and statistical analyses of the data, there were strong relationship between microtexture, macrotexture and types of surface pavement subjected to different dry and wet conditions.
The effect of different degree of compaction towards electrical resistivity value for cohesive soil
Authors: Abd Malik A K , Madun A , Abu Talib M K , Pakir F , Md Dan M F , Abu Bakar N
Published: June 2024

Electrical resistivity is a non-destructive method used to measure the resistivity of ground properties, which is related to soil properties such as porosity and degree of saturation, as described in Archie’s law. In road construction, soil compaction is a crucial process that requires quick quality assessment. Traditional methods, such as sand replacement tests, are time-consuming, limited in coverage, and labour-intensive. Therefore, incorporating electrical resistivity techniques on the current quality control practices may significantly improve efficiency. To achieve this, it is essential to establish the relationship between soil density, moisture content, and electrical resistivity. This study focuses on industrial and natural soil samples compacted using standard proctor moulds using 2.5 kg and 4.5 kg hammers. Resistivity measurements were conducted using the Miller 400A device using Wenner array and 1 cm electrode spacing. The impact of different compaction degrees on electrical resistivity values were compared for the two soil samples. The findings showed that soil dry density increased with the increment of water content until it reached maximum dry density. However, as water content continued to increase, the dry density decreased. Based on the results, electrical resistivity was higher at low water content but reduced with the increments of water contents. The resistivity value for industrial soil decreased from 164 to 12 Ohm.m and 200 to 13 Ohm.m. For natural soil the resistivity value decreased from 45 to 9 Ohm.m and 126 to 11 Ohm.m. The comparison of electrical resistivity values between the two different compaction methods indicated the moisture content limited the capability of the electrical resistivity method to identify the compaction effect in the proctor soil testing. This study demonstrates the potential applicability of electrical resistivity techniques in assessing soil compaction.
Evaluation of Compressed Earth Block (CEB) with the utilization of Durio Zibethinus Fiber (DZF)
Authors: Osman N M , Md Hasan A S , Zakariah Z , Nazir M I M
Published: June 2024

The Compressed Earth Block (CEB) by utilizing the Durio Zibethinus Fiber (DZF) is an innovative idea to promote the Green Initiatives Buildings in the construction industry. The utilization of agricultural waste product which is Durio Zibethinus contribute to minimization of the firing process which involves high energy and emitted high carbon footprint. Rising interest in producing ultimately green and environmentally friendly building materials has opened the initiative to re-use the waste from the agriculture industry, which also reduces the potential pollution source. In this study, the CEB was produced by the addition of durian peel fiber to the brick mix at different percentages of 2%, 3%, and 5% and was assessed for its mechanical and physical properties. On the other hand, the durian fiber was first treated with aluminium sulfate to improve durability and reduce the water absorption rate. With the proper use of a stabilizer, the CEB is proven to demonstrate comparable strength and durability compared to a burnt clay brick. It was found that the 3% durian fiber has produced the optimum compressive strength and decreased the water absorption rate over time.
A Review of Structural Health Monitoring in Heritage Building due to Cracking Issues
Authors: Chik T N T , Mahamood I A , Mohamad N A E , Yusoff N A , Rusidi M A Y , Hakim S J S
Published: June 2024

This paper reviews the application of Structural Health Monitoring (SHM) on heritage buildings due to crack problems. SHM is an essential tool for ensuring the safety and long-term preservation of historic structures. The review focuses on the challenges and opportunities of implementing SHM techniques on heritage buildings, including the use of non-destructive testing, wireless sensor networks, and machine learning algorithms. The paper also highlights case studies of successful SHM implementations on heritage buildings and discusses the importance of integrating SHM into the overall maintenance and preservation strategy for these structures. In general, the article convincingly highlights the critical significance of incorporating SHM in heritage buildings. This practice is essential for guaranteeing the enduring preservation and safety of these buildings, thereby securing their legacy for future generations.
Towards greener concrete: a comprehensive review of waste glass powder as a partial fine aggregate substitute
Authors: Hakim S J S , Mhaya A M , Mokhatar S N , Kamarudin A F , Tong Y G , Chik T N T
Published: June 2024

Concrete typically emerges as the superior choice in terms of strength, adaptability, longevity, noise reduction, energy efficiency, and it additionally possesses the advantage of being fully recyclable. The excessive consumption of natural resources such as sand in traditional concrete production poses environmental concerns and makes concrete production as a significant contributor to greenhouse gas emissions. By using waste glass powder as a partial substitute for fine aggregate, the study explores the potential to lower the carbon footprint of concrete, to reduce the reliance on virgin materials, minimize waste generation, and promote sustainable practices in the construction sector and finally contributing to climate change mitigation and environmental stewardship. Also, it can offer cost savings, as waste glass is often readily available at low cost, reducing the dependence on expensive virgin materials. This article assesses the workability, durability, compressive, flexural, and tensile strength of concrete when waste glass powder is used as a partial substitute for fine aggregate. Additionally, it provides a comprehensive summary of the current state of knowledge on this topic, evaluating the outcomes of previous studies, methodologies, and limitations. This review paper aids in understanding the progress made in this field and identifying areas that require further investigation. Overall, preparing a review paper on the performance of waste glass powder as a partial substitution of fine aggregate in concrete consolidates existing knowledge, evaluates performance, identifies benefits, challenges, and guides future research.
Damage plasticity model for green concrete material
Authors: Bosro M Z M , Mohamad N , Samad A A A , Goh W I , Noranai Z , Tambichik M A , Mokhtar N , Hakim S J S
Published: June 2024

Concrete damage plasticity (CDP) material model is a constitutive material model used to describe the behaviour of reinforced concrete under stress. This model is particularly useful for simulating the response of concrete structures subjected to a wide range of loading conditions. These studies aim to develop the CDP material modelling for green concrete mixture. The mixture proportion of the green concrete material was obtained from previous literature study. The material was then casted into cylindrical specimen purposely to investigate both of their elastic and plastic deformation through axial compression testing. The value of their deformation is measured by the strain gauges attached at their both sides of failure zone. The results shows that the concrete damaged plasticity (CDP) material model value in terms of their compressive crushing and tensile cracking damage. The value for compressive crushing damage was 0.0000000, 0.0000000, 0.0000000, 0.2087821, 0.4888152, 0.6959403, 0.8077879 and 0.9113505. Meanwhile, the value for tensile cracking damage was 0.00000, 0.12705, 0.25410, 0.45492, 0.56635, 0.62295, 0.68415, 0.74118, 0.79098, 0.85371 and 0.90164. By using this green concrete damage plasticity (CDP) material model, engineers and researchers can make more accurate predictions about the performance of green concrete structures, leading to safer and more cost-effective designs.
Effect of green mussel (Perna Veridis) shell powder as partial fine aggregate replacement on the mechanical properties of concrete
Authors: Nagor Maidin M M , Othman N H , Sulaiman N , Sainudin M S , Abdul Hamid N A , Ayop S S
Published: June 2024

Depletion of natural resources is one of sustainability problem which requirement to address in efficiently. Nowadays, the trend in construction industry is to use the alternative source of construction materials which can substitute the use of new materials. The aim of this attempts is to reduce environmental impact in terms of energy consumption, pollution, waste disposal and global warming. As an alternative solution to reduce waste quantity by utilizing it in construction materials. Thus, this study was carried out to identify the physical properties of the mussel shell powder as partial fine aggregate replacement and to define the optimum percentage of mussel shell powder in concrete based on its physical and mechanical properties. The percentage of mussel shells powder used in this study were 0%, 10%, 20% and 30% (C100, C10MSP, C20MSP and C30MSP). The total 48 cubes sample size, 100mm x 100mm x 100mm were used and tested on its compressive strength and capillary water absorption test for 7 and 28 curing days. The result shows that specific gravity of fine aggregate is lower than mussel shells powder which was 2.76 and 2.90. Based on compressive strength resulted, C20MSP has high strength (35.9 MPa) compare to another concrete mixes. While for the water capillary absorption resulted that C30MSP has the low average water capillary absorption (0.12cm/s). Therefore, for the mechanical properties of this research, it can be concluded that mussel shell replacement should be in average between 20% to 30% of fine aggregates. Furthermore, the high content of calcium carbonate (CaCO3) in chemical composition of mussel shell powder act as a filler in concrete and promoting early hydration process.
The use of coffee waste in bio-foamed concrete brick (B-FCB) to reduce the penetration of carbon dioxide (CO2) into concrete
Authors: Alshalif Abdullah Faisal , Azril Y M , Irwan J M , Mutafi A , Alshaeer Honin Ali Yahya , Hakim S J S
Published: June 2024

The aim of this study was to examine the potential of coffee waste (CW) in reducing the carbonation of bio-foamed concrete brick (B-FCB). This study utilised coffee waste (CW) as an alternative material to replace cement, with different concentrations of 1%, 5%, and 10%. Furthermore, the utilisation of Bacillus tequilensis (B. tequilensis) was employed with the objective of achieving self-healing. A 2k factorial design was employed to perform a statistical analysis aiming to optimise the carbonation depth of B-FCB incorporating CW for a duration of 28 days. The experiment consisted of 11 runs. The performance of carbonation depth as response of this study was monitored with three main factors namely the density of concrete (D), coffee waste (CW), and B. tequilensis (B), respectively. The factors were bounded by upper and lower limits of 1300 kg/m3 and 1800 kg/m3, 1% and 10%, and 3x105 cell/ml and 3x107 cell/ml, respectively. The study established that the ideal carbonation depth was 8 mm, based on specific conditions as follow; 1300 kg/m3 of concrete D, 1% of CW and 3×105 cell/ml of B at 28 days. On the other hand, it was observed that the carbonation depth had a value of zero when the cement was replaced with 10% CW in runs 5, 6, 7, and 8. The empirical findings illustrate the effects of (CW) on reducing the level of carbonation in B-FCB, hence promoting its long-term sustainability.
Utilization of Dry Tailing as Mortar Filler in Bricks
Authors: Cintiya D , Adriati F , Ihsan M , Rasyif T M
Published: June 2024

Tailing is a hazardous waste generated from the gold mining process. This research was conducted in Poboya Village, Central Sulawesi, with the aim of reducing environmental impact and utilizing hazardous waste (B3 waste). The tailing processing method employed the dry stacking technique with a filter press, resulting in dried tailings with a moisture content of 5%-20% And already meets the target moisture level during the filter press process, which is 18 - 25%. In this study, laboratory tests were conducted to examine the mechanical characteristics of dry tailings as a cement mixture in the production of bricks. The tests included sieve analysis, hydrometer tests, moisture content, weight volume, specific gravity, unit weight, cement hydration binding time, and compressive strength. Brick composition variations involved the use of 0%, 10%, 20%, and 30% dry tailings as partial sand substitutes. The test results indicated that the use of dry tailings up to 30% as a sand substitute did not meet the brick compressive strength standards set by the SNI 03-0349-1989 standard. Variations in compressive strength results among samples displayed significant differences, potentially due to factors such as molding, environment, and testing procedures. The utilization of a significant amount of tailings tended to decrease brick compressive strength. Despite not achieving the desired compressive strength values in bricks, this study showcased the potential to utilize dry tailings as a mixture material in construction. With further research and optimization of mixture compositions, the potential for reusing dry tailings in construction materials could be maximized.
Stability of Orthotropic Runway Plate under The Combination In-Plane and Transversal Dynamic Loads on Kerr Foundation Soil Modelling
Authors: Reza M D F , Alisjahbana S W , Rasyif T M
Published: June 2024

Runway pavements are subjected to dynamic loads from aircraft landing and take-off, which can cause vibrations and lead to cracking and instability. The existing method for designing runway pavements, the ACN-PCN method, does not consider the effects of vibration, deflection, and external loads. This research proposes a new approach for designing runway pavements using a numerical method that accounts for these factors. The method uses differential and Kerr foundation equations with the Levy method to determine the deflection of the plate structure. The soil parameters are obtained from soil sampling, and the loads are designed based on previous studies and government regulations. The results of the research show that the soil characteristic has the greatest impact on the deflection of the plate. A harder soil will result in less deflection, which is important for the safe operation of the runway. A thicker plate also exhibits increased stiffness and reduced deflection. In-plane compressive loads can increase the potential for plate bending, which can compromise the structural integrity of the plate.
The effect on tensile and surface morphological properties of oil palm empty fruit bunch fibre through hot water treatment
Authors: Abu Bakar H , Ismail L H , Nik Soh N M Z , Samsudin E M , Astimar A A
Published: June 2024

The utilisation of Oil Palm Empty Fruit Bunch (EFB) fibre, a significant crop in Malaysia, is a viable option for incorporation into cement-based products due to the substantial amount of waste it generates. Nevertheless, the presence of extractives has a significant impact on the performance of EFB fibre and leads to an inherent incompatibility between EFB fibre and cement. Hence, the purpose of this study was to investigate the impact of varied temperatures and soaking durations on the physical and mechanical properties of EFB fibre as a reinforcement material. This research aimed to contribute new insights into the performance of these qualities under varying conditions. The result from the tensile strength shows that the EFB fibre increased dramatically with temperature at all soaking times. Nevertheless, extended periods of soaking have been found to have a detrimental effect on the tensile strength of fibres due to the process of deterioration. This leads to a weakening or damage to the fibres. Thus, the surface morphology observation proved that as temperature increased, the number of silica bodies removed from the fibre surface increased (80°C, 90°C and 100°C) at all soaking hours. However, starting at 70°C (3 hour soaking time), the circular craters on the surface and the lignin layer start to damage. Therefore, these findings exhibit considerable potential for future investigation in substantiating the viability of employing EFB fibres as reinforcement agents in composite materials.
Review on metakaolin impact on the workability and compressive strength of concrete
Authors: Kamal M A H , Salleh N , Hamid N A A , Jamellodin Z , Ali N , Abdullah S R , Adnan S H
Published: June 2024

The utilization of supplementary cementitious materials (SCMs) in concrete production has gained considerable attention in recent years, driven by the need for sustainable construction practices and improved concrete performance. Among these materials, metakaolin has emerged as a promising mineral admixture due to its pozzolanic properties and potential to enhance various aspects of concrete behavior. This review examines the extensive research conducted to evaluate the impact of metakaolin on both the workability and compressive strength of concrete. Metakaolin’s influence on compressive strength is due to its pozzolanic reactivity, which contributes to the formation of additional calcium silicate hydrate gel and refined microstructure. Metakaolin addition enhances concrete’s workability and compressive strength, improving ease of mixing and placement. It absorbs water and increases viscosity but can reduce workability by up to 20% and the optimum replacement ratio is between 5% and 15%. Metakaolin significantly impacts concrete workability and compressive strength, with its high reactivity and pozzolanic characteristics causing challenges. However, careful mix design adjustments and incorporation strategies can effectively address these issues. Metakaolin’s contribution to supplementary cementitious reactions and microstructural refinement highlights its potential as a valuable addition to concrete mixtures. Metakaolin’s contribution to supplementary cementitious reactions and microstructural refinement enhances compressive strength, making it a valuable addition to concrete mixtures. Further research on metakaolin’s interactions with concrete constituents will contribute to sustainable and high-performance concrete solutions in the future.
Dynamic Response of Orthotropic Plate Due to Local Friedlander Blast Loads On Kerr Foundation Soil Modeling
Authors: Furqan M N , Alisjahbana S W , Rasyif T M
Published: June 2024

The development of infrastructure design is getting more advanced, there are more and more things that need to be considered in designing an infrastructure and a building, the effect of blast loads needs to be considered. Explosion load itself is one of the dynamic loads that can burden a structure beyond its normal loading conditions. Therefore, it is necessary to have special planning for an infrastructure and building so that if an explosion occurs it can minimize serious damage to the structure of the infrastructure and building. In this study, the focus is on orthotropic plates with semi-rigid bearings on the Kerr foundation soil model due to local Friedlander blast loads. Variations in plate thickness and soil type were carried out to determine the dynamic response on the plate that would arise due to the local Friedlander blast load. Utilizing the Modified Bolotin Method (MBM) analysis technique to solve it through the Wolfram Mathematica program. Based on the numerical tests that were conducted, it is found that the type of soil is directly proportional to the natural frequency value, indicating that stiffer soil types result in higher natural frequencies, signifying a stiffer response to floor plates. Thicker plates result in smaller deflections with the same soil type. These numerical results can serve as design guidelines for structures under blast loads.
A perfusable, vascularized kidney organoid-on-chip model
Authors: Kroll Katharina T , Homan Kimberly A , Uzel Sebastien G M , Mata Mariana M , Wolf Kayla J , Rubins Jonathan E , Lewis Jennifer A
Published: June 2024

The ability to controllably perfuse kidney organoids would better recapitulate the native tissue microenvironment for applications ranging from drug testing to therapeutic use. Here, we report a perfusable, vascularized kidney organoid on chip model composed of two individually addressable channels embedded in an extracellular matrix (ECM). The channels are respectively seeded with kidney organoids and human umbilical vein endothelial cells that form a confluent endothelium (macrovessel). During perfusion, endogenous endothelial cells present within the kidney organoids migrate through the ECM towards the macrovessel, where they form lumen-on-lumen anastomoses that are supported by stromal-like cells. Once micro-macrovessel integration is achieved, we introduced fluorescently labeled dextran of varying molecular weight and red blood cells into the macrovessel, which are transported through the microvascular network to the glomerular epithelia within the kidney organoids. Our approach for achieving controlled organoid perfusion opens new avenues for generating other perfused human tissues.
Bayesian parameter estimation and evaluation of the K-ω shear stress transport model for plane impinging jets
Authors: Lanahan M L , Abdel-Khalik S I , Yoda M
Published: June 2024

Numerical simulations with semi-empirical turbulence models are commonly used to model impinging jets, often used for cooling solid surfaces. In this work, the constants in the k-ω shear stress transport model in ANSYS FLUENT are calibrated to experimental velocity and heat transfer data for a plane turbulent impinging air jet to determine if Kennedy-O’Hagan calibration (Kennedy and O’Hagan 2001 J. R. Stat. Soc. B 63 425–64) can improve predictions of near-surface velocities and surface Nusselt numbers for similar flows. Impinging jets have been proposed to cool the target plates of the divertor in future magnetic fusion energy reactors, where simulations are used to estimate divertor performance. The flat-plate divertor (Wang et al 2009 Fusion Sci. Technol.
56 1023–7) uses a plane jet of helium issuing from a B = 0.5 mm slot to cool a surface with radius of curvature of 44B at a distance 4B from the slot. Predictions from the calibrated numerical model are compared with independent experimental data at different flow conditions, as well as surface temperature data for a flat plate divertor test section. The contribution of this work is evaluation of the accuracy of a calibrated turbulence model for modest extrapolations in flow geometry and flow conditions for a plane impinging jet.
Assessment of water quality, heavy metal pollution and human health risks in the Canal system of Ho Chi Minh City, Vietnam
Authors: Tong Nguyen Xuan , Thao Nguyen Thi Thanh , Anh Le Hung
Published: June 2024

This study was conducted to determine the surface water quality and health risks in Ho Chi Minh City (HCMC) canals. 180 water samples and 180 sediment samples were collected from 15 canal locations in HCMC in 2021 and 2022. The Water Quality Index (WQI) assessment results indicated that the water quality in 2021 ranged from unsuitable to good, with a trend towards improvement in 2022, where good quality water was predominant. TMs PCA/FA identified domestic and agricultural wastewater from HCMC residents as influencing the water quality. Most TMs detected in surface water were within the limits the Vietnamese Ministry of Natural Resources and Environment allowed, except for Pb in 2022 (> 0.02 mg l−1). For sediments, TMs concentrations were higher than in water samples but showed a decreasing trend over the survey period in the order of Hg < Cd < As < Pb < Cu. The findings show that sediments are more strongly affected by TMs than surface water, with the main sources being industrial and agricultural human activities. The non-cancer risk assessment showed that children are more exposed to TMs than adults, mainly through ingestion. Additionally, the cancer risk assessment (CR) identified As in sediments as posing an unacceptable cancer risk (TCR > 1 × 10−4). Therefore, it is necessary to establish high-frequency monitoring policies to analyze and reduce TMs concentrations in water and sediments of the canals to protect human health.
In-situ topotactic chemical reaction for spectroscopies
Authors: Kawakami Tappei , Nakayama Kosuke , Sugawara Katsuaki , Sato Takafumi
Published: June 2024

Topotactic chemical reaction (TCR) is a chemical process that transforms one crystalline phase to another while maintaining one or more of the original structural frameworks, typically induced by the local insertion, removal, or replacement of atoms in a crystal. The utilization of TCR in atomic-layer materials and surfaces of bulk crystals leads to exotic quantum phases, as highlighted by the control of topological phases, the emergence of two-dimensional (2D) superconductivity, and the realization of 2D ferromagnetism. Advanced surface-sensitive spectroscopies such as angle-resolved photoemission spectroscopy and scanning tunneling microscopy are leading techniques to visualize the electronic structure of such exotic states and provide us a guide to further functionalize material properties. In this review article, we summarize the recent progress in this field, with particular emphasis on intriguing results obtained by combining spectroscopies and TCR in thin films.
Experimental and finite element analysis of tensile properties of oil palm trunk im–pregnated with epoxy
Authors: Nik Wan F , Abubakar A , Suriani M J , Saat A M , Fitriadhy A , Wan Nik W M N , Abdul Majid M S , Mukhtar Z Z , Ilyas R A , Mohd Nurazzi N , Norrrahim M N F
Published: June 2024

This research focuses on determining the elastic properties from the development of a three-dimensional constitutive model of impregnated oil palm trunk reinforced with epoxy (OPTE) composite. The research aims to simulate the tensile behaviour of OPTE composite for finite element analysis and compared with the OPTE experimental results, respectively. The OPTE composites were manufactured by using one of the vacuum infusion techniques namely the vacuum-assisted resin transfer moulding technique. In this research, OPTE composite is considered as a unidirectional fibre due to the wood board in the resin. Tensile tests were conducted to provide the material properties as inputs into three-dimensional constitutive model. The tensile test was performed according to ASTM D3039. The test was divided into three zones including zone I (outer), zone II (middle) and zone III (inner). The three elastic constants (elastic modulus, shear modulus and Poisson’s ratio) of material properties were obtained from the tensile test data and theoretical equation. The model was developed in Abaqus software. The results from finite element method (FEM) were compared with the experimental results. There was a good agreement and promising results between FEM and the experimental data.
The futility of being selfish in vaccine distribution
Authors: Alves Felippe , Saad David
Published: June 2024

We study vaccine budget-sharing strategies in the SIR (Susceptible-Infected-Recovered) model given a structured community network to investigate the benefit of sharing vaccine across communities. The network studied comprises two communities, one of which controls vaccine budget and may share it with the other. Different scenarios are considered regarding the connectivity between communities, infection rates and the unvaccinated fraction of the population. Properties of the SIR model facilitates the use of dynamic message passing (DMP) and optimal control methods to investigate preventive and reactive budget-sharing scenarios. Our results show a large set of budget-sharing strategies in which the sharing community benefits from the reduced global infection rates with no detrimental impact on its local infection rate.
Operator estimates for homogenization of higher-order elliptic operators with periodic coefficients
Authors: Sloushch V. , Suslina T.
Published: June 2024

In

L
2

(

R

d

;

C

n

)

L_2(\mathbb {R}^d;\mathbb {C}^n)

, a strongly elliptic differential operator

A

ε

{\mathcal {A}}_\varepsilon

of order

2
p

2p

is studied. Its coefficients are periodic and depend on

x

/

ε

\mathbf {x}/\varepsilon

. The resolvent

(

A

ε

+
I

)

−
1

({\mathcal {A}}_\varepsilon +I)^{-1}

is approximated in the operator norm on

L
2

(

R

d

;

C

n

)

L_2(\mathbb {R}^d;\mathbb {C}^n)

:
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="left-parenthesis script upper A Subscript epsilon Baseline plus upper I right-parenthesis Superscript negative 1 Baseline equals left-parenthesis script upper A Superscript 0 Baseline plus upper I right-parenthesis Superscript negative 1 Baseline plus sigma-summation Underscript j equals 1 Overscript 2 p minus 1 Endscripts epsilon Superscript j Baseline script upper K Subscript j comma epsilon Baseline plus upper O left-parenthesis epsilon Superscript 2 p Baseline right-parenthesis period">

(

A

ε

+
I

)

−
1

=
(

A

0

+
I

)

−
1

+

∑

j
=
1

2
p
−
1

ε

j

K

j
,
ε

+
O
(

ε

2
p

)
.

\begin{equation*} ({\mathcal {A}}_\varepsilon +I)^{-1} = ({\mathcal {A}}^0+I)^{-1} + \sum _{j=1}^{2p-1} \varepsilon ^{j} {\mathcal {K}}_{j,\varepsilon } + O(\varepsilon ^{2p}). \end{equation*}

Here

A

0

{\mathcal {A}}^0

is an effective operator with constant coefficients, and

K

j
,
ε

{\mathcal {K}}_{j,\varepsilon }

,

j
=
1
,
…
,
2
p
−
1

j=1,\dots ,2p-1

, are appropriate correctors.
Chaplaincy and Seafarers
Authors: Sampson Helen , Turgo Nelson , Cadge Wendy , Gilliat-Ray Sophie
Published: June 2024

This book explores the faith, work, and lives of seafarers and port chaplains. These two groups of people are frequently overlooked by academics, as well as by members of wider society. Ports and ships are largely inaccessible to the public. As a result of their lack of visibility, many people are oblivious to the duties, needs, hopes, and aspirations of port chaplains and seafarers. This book therefore offers a rare insight into the life worlds of two little-known groups of workers. The book takes a broadly sociological approach and combines ethnographic and qualitative methodologies. It draws on the findings of a comprehensive study that was funded by the Economic and Social Research Council. The research involved the analysis of archive materials, fieldwork in ports and on cargo ships, and interviews with chaplains in the United Kingdom, chaplains overseas, and stakeholder organizations. Using these sources, the text provides a detailed account of seafarers’ attitudes to working in mixed-faith crews, their understandings of their own faith and its role and negotiation in a life at sea, and their needs with regard to faith and more general welfare support. In addition, it details the daily life and work of port chaplains and explains how they understand their roles in relation to their own faith, as well as how they manage their work in a multi-faith environment.
Introduction
Authors: Sampson Helen , Turgo Nelson , Cadge Wendy , Gilliat-Ray Sophie
Published: June 2024

The introduction begins by describing some of the key characteristics of the shipping industry. It explains the role of port chaplains in providing seafarers with support while they are working on board and the overall importance of port welfare providers to such seafarers. It describes the background, aims, and underpinning evidence for the book and describes the large, multifaceted study funded by the Economic and Social Research Council that took place in the period 2017–2021 on the life, work, faith, and welfare needs of seafarers. It outlines the structure of the book and provides a brief synopsis for each of the chapters.
The Work of Contemporary Port Chaplains
Authors: Sampson Helen , Turgo Nelson , Cadge Wendy , Gilliat-Ray Sophie
Published: June 2024

Chapter 2 presents a detailed account of the daily work of port chaplains. It describes their day-to-day activities and the assistance they provide to seafarers. The chapter describes some of the challenges they face in carrying out their work. These include the demanding nature of the work in relation to emotional labour, financial constraints, and ecumenical approaches to port welfare provision. Drawing upon field notes and the testimony of chaplains themselves (in the form of quotes from interview transcripts), the chapter offers a rich flavour of what it is that port chaplains do, how they do it, and the challenges which they face in trying to do their job.
Practical Ecumenical Cooperation amongst Organizations Providing Port Chaplaincy
Authors: Sampson Helen , Turgo Nelson , Cadge Wendy , Gilliat-Ray Sophie
Published: June 2024

Caring for seafarers is a global collaborative effort between individuals working for organizations affiliated with secular and religious charities. Chapter 7 examines the ways that the charitable organizations supporting port chaplaincy have embraced ecumenism and ecumenical working practices and the consequences of this for the day-to-day work of port chaplains. A major initiative that has been taken by cash strapped charities has been to combine resources and co-locate service provision. Although working from the same building is economically efficient it has sometimes given rise to tensions between members of different welfare charities, which may be associated with individual personalities and also differing theologies. This chapter focuses on commonalities and differences between welfare workers from different organizations and how these play out in relation to the day-to-day work of port chaplains and the support that they provide to seafarers.