bluuebunny/crossref_metadata_2025 huggingface dataset:
Calculated cross sections for electron collisions with the BeN molecule
Authors: Chakrabarti K , Dinda S
Published: July 2023

We report a low energy electron collision calculation with the BeN molecule in its X

4

Σ
−

ground state using the molecular R-matrix method at a single geometry, namely, the equilibrium

R
e

=
3.045

a
0 of the molecule. Using a suitable target model, we have calculated the elastic cross section and cross sections for electron impact excitation in several low-lying excited states of BeN. Cross sections for electron impact dissociation is derived from the electronic excitation cross sections. In addition, molecular data on bound sates of BeN and e-BeN negative ion resonances and widths at the target equilibrium Re
that may be relevant for other studies are also provided.
Optimization of elastic wave propagation in a reconfigurable medium by genetic algorithms with adaptive mutation probability
Authors: Rus Janez , Fleury Romain
Published: July 2023

We introduce a reconfigurable medium for the manipulation of elastic propagation properties of Lamb waves. It is based on a shape memory polymer (SMP) with temperature-dependent Young’s modulus. Waves are excited by a laser pulse and detected by a laser vibrometer. A two-dimensional temperature field is controlled by a scanning heating laser. We use genetic algorithms to determine optimal distributions of mechanical properties for the following criteria: the wave amplitude has to be maximized at a given location and at the same time minimized at one or two other locations. Due to the reconfigurability of the medium, the optimization process is performed directly on the object of optimization, and not on a numerical or analytical representative, based on a direct measurement of the fitness. The optimized configuration makes the waves propagate away from (or around) the point of minimization towards the point of maximization. We improve the genetic algorithm by adapting the mutation probability of individual genes according to specific criteria, which depend on the surrounding genes (distributed in two dimensions). This provides the advantages: concentrating the mutations in the areas of genetic inconsistencies and counterbalancing the error of the fitness measurement. The method is applicable for the intelligent design of wave energy harvesters, ultrasonic transducers, and analogue wave computing devices.
The effect of temperature on guided wave signal characteristics in presence of disbond and delamination for health monitoring of a honeycomb composite sandwich structure with built-in PZT network
Authors: B Ramana Raja , Patil Sheetal , Kashyap Pankhi , Tallur Siddharth , Banerjee Sauvik
Published: July 2023

Guided wave (GW) based structural health monitoring (SHM) techniques being developed by researchers frequently use amplitude and group velocity variations between healthy and damage-affected GW modes to detect and localise damage. Nonetheless, external variables such as temperature and moisture influence these features, which were not considered in previous studies, particularly in the presence of damage in honeycomb composite sandwich structures (HCSSs). Therefore, a coordinated numerical and experimental study was carried out in an effort to examine the characteristics of GW propagation in an HCSS for two damages: a disbond between the face sheet and the core, and delamination between the face sheet layers for a temperature range of 0 ∘C–90 ∘C. Computationally efficient two-dimensional numerical models were developed using COMSOL Multiphysics that takes into account a variety of temperature-related phenomena, such as thermal stresses and changes in the material properties of honeycomb sandwich and piezoelectric wafer transducers (PZTs). The amplitude and group velocity of the fundamental anti-symmetric (A0) mode are found to increase in the presence of a disbond and decrease in the presence of face sheet delamination. However, it is observed that there is a linear decrease in the amplitude of A0 mode for both the healthy and damaged cases with an increase in temperature. Since the A0 mode is widely employed for interrogation due to its defect sensitivity, an amplitude and group velocity adjustment equation with temperature change is proposed. Finally, considering the amplitude difference of normalised A0 mode, the two damages are localised within a network of PZTs by using a probability-based signal difference coefficient method, which is found to be efficient and reliable for SHM of HCSS under variable temperature conditions.
Smart fault detection of HTS coils using artificial intelligence techniques for large-scale superconducting electric transport applications
Authors: Yazdani-Asrami Mohammad , Fang Lurui , Pei Xiaoze , Song Wenjuan
Published: July 2023

Superconducting coil is an essential and critical component in any superconducting apparatus used in large-scale power applications such as in superconducting machines of propulsion systems, in fault current limiters of the distribution system for future cryo-electric aircraft, or in windings of superconducting transformers for power grid applications. The superconducting coils in winding of large-scale power devices operate in kind of harsh environments from both temperature—considering liquid hydrogen or gaseous helium as coolant—(thermal stress) and electro-magneto-mechanical stress, point of views. Reliable operation of the coils in winding is of vital importance for the reliability of the superconducting device and the safety of the application that the device is used for. If the superconducting coil confronts a fault or an abnormal condition in the laboratory-level operation, it is straightforward to test the coil by measuring its critical current, AC loss, etc, to find whether it is damaged or not. However, there would be an urgent need to have faster and more intelligent fault detection and condition monitoring approaches with the possibility to become fully autonomous and real-time, in large-scale power applications, especially in sensitive applications such as in future cryo-electric aircraft, or in the fusion industry. To reach such intelligent fault-finding approaches, artificial intelligence-based techniques have been foreseen to be a promising solution. In this paper, we have developed an intelligent fault detection technique for finding a faulty superconducting coil, named the frequency-temporal classification method. This method has two main steps: first, this paper utilizes the discrete Fourier transform and independent component analysis to convert measurement signals of the healthy and faulty coils from (1) the time-series domain to the frequency domain; and (2) into time-series source signals. Second, this paper trains the support-vector machine using the derived frequency components. This trained model is then used for making fault detection for other superconducting coils. The developed technique can classify a fault with 99.2% accuracy.
Low-resistance joints for YBCO-coated conductors with Ag nanoparticle paste
Authors: Wang Wentao , Wang Ming , Han Leilei , Chen Yu , Liu Lian , Yang Fan , Li Mingyu , Yu Zhou , Zhao Yong
Published: July 2023

Due to the limited available piece length of YBCO-coated conductors (i.e. tapes or wires) and the different requirements for magnetic field, joints are inevitable for manufacturing high-temperature superconducting magnets. In this study, a sintering nano-silver (Ag) process was developed and used to connect YBCO tapes stabilized by anAg layer with low-temperature and short-time sintering of Ag nanoparticle (NP) paste. The thermodynamic characteristics of Ag NP paste were explored using a TG/DSC setup. The effects of sintering temperature, mechanical pressure and lapped length on microstructures and electrical properties of joints were comprehensively investigated. It is found that the pre-volatilization of low-boiling-point solvent in the paste is beneficial to improve the densification of sintered structure, thus contributing to increasing the critical current I
c of the joint. With increasing sintering temperature, the I
c of the joint will be close to that of the virgin tape, and the joint resistance experiences small fluctuations, but joint connectivity is enhanced. As the temperature reaches 205 °C, I
c decreases to 84% of the virgin tape, and joint resistance increases obviously. In addition, the axial tension strength at room temperature is improved with the increase in mechanical pressure, while the resistance does not demonstrate distinct variation. Considering the electromechanical properties, the optimal joining process is determined as sintering at 180 °C and 30 MPa for 10 min. The joint with this technology possesses a closely connected interface and a well-sintered nano-Ag microstructure with pores. By further extending the lapped length, a YBCO joint resistivity as low as ∼10.56 nΩ cm2 is obtained, which is around a quarter of that of the soldering joint, and the process is much easier than that of the Ag diffusion joint.
Long-range temperature-controlled transport of ultra-cold atoms with an accelerated lattice
Authors: Absil L , Balland Y , Pereira Dos Santos F
Published: July 2023

We report our method for transporting ultracold atoms over macroscopic distances and trapping them back in a vertical mixed trap, consisting of the superposition of a vertical lattice and a transverse confinement beam. The transport is performed with Bloch oscillations allowing us to move up to

25
%

of a sub-micro-Kelvin atomic cloud on a distance of the order of 30 cm, without excessive heating and with an excellent control of its final position. The efficiency is lowered to about

10
%

after trapping them in the vertical mixed trap during extended times.
Interaction and dragging of 2,4-D molecules in SPC/E water by (6,5) carbon nanotubes at ambient pressure
Authors: Castellanos-Aldama André Fabián , González-Melchor Minerva
Published: July 2023

We present a computer simulation study of the herbicide 2,4-dichlorophenoxyacetic acid, interacting with a single-walled (6,5) carbon nanotube in water. Our study was conducted at 1 bar of pressure, and the temperature varied from 280 to 370 K. Pair correlation functions, coordination number, water hydrogen bonding, density, static dielectric constant, and interaction energy between the nanotube and acid molecules, were determined. Mean square displacement and self-diffusion were also obtained. Our results showed that the herbicide molecules and the nanotube form a complex. Pair correlation functions revealed that acid molecules are most likely found at a distance of 7.4 Å from the nanotube and are located within 20 Å of it. Water hydrogen bonding and dielectric behavior of the mixture were similar to those of pure water. The mean square displacement revealed an incipient plateau located between two regions of linear behavior, which might be related to the frequent coming and going of 2,4-D molecules around the nanotube. The diffusion coefficient of 2,4-D was higher than that of the nanotube. Our results show a trend similar to that revealed in experiments on the capture of 2,4-D herbicide by (6,5) carbon nanotubes, indicating that the interaction parameters here used, produce a reasonable description of the calculated properties. As a general conclusion, our data support the idea that using carbon nanotubes in domestic devices for the dragging and removal of 2,4-D herbicide from water might be feasible.
Scalar dark matter vortex stabilization with black holes
Authors: Glennon Noah , Mirasola Anthony E. , Musoke Nathan , Neyrinck Mark C. , Prescod-Weinstein Chanda
Published: July 2023

Galaxies and their dark-matter halos are commonly presupposed to spin. But it is an open question how this spin manifests in halos and soliton cores made of scalar dark matter (SDM, including fuzzy/wave/ultralight-axion dark matter). One way spin could manifest in a necessarily irrotational SDM velocity field is with a vortex. But recent results have cast doubt on this scenario, finding that vortices are generally unstable except with substantial repulsive self-interaction. In this paper, we introduce an alternative route to stability: in both (non-relativistic) analytic calculations and simulations, a black hole or other central mass at least as massive as a soliton can stabilize a vortex within it. This conclusion may also apply to AU-scale halos bound to the sun and stellar-mass-scale Bose stars.
Test of conformal theory of gravity as an alternative paradigm to dark matter hypothesis from gravitational
lensing studies
Authors: Ghosh Shubhrangshu , Bhattacharya Mahasweta , Sherpa Yanzi , Bhadra Arunava
Published: July 2023

Weyl's conformal gravity theory, which is considered as a compelling alternative to
general relativity theory, has been claimed to describe the observed flat rotation curve feature
of spiral galaxies without the need of invoking dark matter. However, it is important to examine
whether the Weyl theory can also explain the relevant gravitational lensing observations correctly
without considering any dark matter. In this regard, the gravitational bending angle in static
spherically space-time (Mannheim-Kazanas metric) in Weyl theory has been calculated by several
authors over the last two decades, but the results are found largely divergent. In this work, we
have revisited the problem and obtain the correct and consistent expression of the deflection
angle in conformal gravity. Subsequently we perform the gravitational lensing analysis. We compare
the prediction of Weyl gravity with the gravitational lensing observations of the rich galaxy
clusters Abell 370 and Abell 2390 and is found that Weyl theory cannot describe the stated lensing
observations without considering dark matter.
Localization of 𝖴(1) gauge field by non-minimal coupling with gravity in braneworlds
Authors: Zhao Zhen-Hua , Xie Qun-Ying , Fu Chun-E. , Zhou Xiang-Nan
Published: July 2023

In this paper, we investigate the localization of the U(1) gauge field on Randall-Sundrum-like braneworld models.
The localization of the U(1) gauge field is important because it plays a fundamental role in the branworld theories.
To achieve the localization, we propose a novel action with a non-minimal coupling between the U(1) gauge field and gravity.
We find that the mass spectrum of the gauge field is continuous, without any gap between the zero-mass mode and the massive modes, and except for the zero-mass mode all the massive modes are not localized on the brane.
Furthermore, the massive modes have negative squared masses, indicating they are tachyonic.
Our analysis can be applied to a wide range of thin and thick braneworld scenarios, provided that the five-dimensional spacetime is asymptotically anti-de Sitter.
Inflationary α-attractor models with singular derivative of potential
Authors: Kubota Kei-ichiro , Matsui Hiroki , Terada Takahiro
Published: July 2023

A generalization of inflationary α-attractor models (polynomial α-attractor) was recently proposed by Kallosh and Linde, in which the potential involves logarithmic functions of the inflaton so that the derivative of the potential but not potential itself has a singularity.
We find that the models can lead to viable inflationary observables even without the pole in the kinetic term.
Also, the generalization with a pole order other than two does not significantly change the functional form of the potential.
This allows a systematic analysis of the predictions of this class of models.
Our models predict larger spectral index ns
and tensor-to-scalar ratio r than in the polynomial α-attractor: typically, ns
around 0.97–0.98 and r observable by LiteBIRD.
Taking advantage of the relatively large ns
, we discuss the modification of the potential to produce primordial black holes as the whole dark matter and gravitational waves induced by curvature perturbations detectable by LISA and BBO/DECIGO, while keeping ns
in agreement with the Planck/BICEP/Keck data.
Characterisation of hydrophone sensitivity with temperature using a broadband laser-generated ultrasound source
Authors: Bakaric Marina , Ogunlade Olumide , Miloro Piero , Zeqiri Bajram , Cox Benjamin T , Treeby Bradley E
Published: July 2023

In this work, we present a novel method for characterising the relative variation in hydrophone sensitivity with temperature, addressing a key aspect of measurements in the field of ultrasound metrology. Our study focused on a selection of miniature ultrasonic hydrophones commonly used in medical applications. The method is based on using water as a temperature-sensitive laser-generated ultrasound (LGUS) source for calibration, allowing for flexible characterisation across a wide temperature range. The measurements were performed using both the LGUS method and the established self-reciprocity method. Our results demonstrate good agreement within 5% between the two methods, validating the effectiveness of the LGUS approach. We found that the sensitivity of the tested hydrophones exhibited low temperature dependence less than −0.2% per ∘C within the studied temperature range from 17 ∘C up to 50 ∘C. The presented LGUS method offers greater flexibility than current approaches as it allows for characterisation of membrane hydrophones with small element sizes and non-electrical transducers. By combining the relative sensitivity variation obtained through the LGUS method with the standard calibration at room temperature, absolute values of hydrophone sensitivity can be determined. The expanded uncertainty of our measurements, which was evaluated at temperature intervals of 8 ∘C, was determined to be on average 10%. Our work provides valuable insights into the temperature dependence of hydrophone sensitivity and lays the foundation for further investigations in this area. The LGUS method holds promise for future enhancements, such as increased bandwidth of the LGUS source and frequency domain analysis, to explore the frequency dependency of sensitivity variation with temperature.
Time-dependent collisional radiative modeling of tungsten in the magnetic sheath for erosion diagnosis
Authors: Johnson C.A. , Ennis D.A. , Loch S.D. , Ballance C.P.
Published: July 2023

Tungsten is the material of choice for the divertors in ITER, SPARC and future fusion reactors. Accurate diagnosis of tungsten erosion and migration is important for first wall life time, slag production and core performance. The addition of a magnetic presheath requires time-dependent collisional radiative effects to be included for accurate neutral tungsten collisional radiative modeling. Gross erosion measurements could be modified by a factor of 10 due to the inclusion of time-dependent effects for ITER relevant divertor conditions. A simple sputtering model and sheath density model are developed to investigate time-dependent collisional radiative effects. Neutral tungsten spectral lines populated from different metastable levels depend on model parameters leading to potential spectroscopic diagnostics of plasma parameters. Electron temperatures inferred from spectroscopic line ratios are in agreement with Langmuir probe measurements in the Compact Toroidal Hybrid.
Recovery of biogas from food waste using treated and untreated anaerobic digestion
Authors: Wid N , Raudin N
Published: July 2023

Biogas is an environmentally friendly, clean, and low-cost renewable energy source. This alternate sustainable source can be used for heat, power, or fuel and making it a good alternative for renewable energy. Biogas can be produced through anaerobic digestion of biodegradable organic materials without oxygen and can be improved by performing thermal treatment. In this study, biogas was recovered using treated and untreated food waste. The characterisation of food waste for its suitability for an anaerobic digestion process was studied by its total solids, volatile solids, pH value, and C/N ratio, following the APHA standard. The anaerobic digestion was treated in a water bath at a temperature of 70 °C for 45 minutes. The Biochemical Methane Potential method was conducted to determine the biogas production from treated and untreated anaerobic digestion. The treated and untreated anaerobic digestion were anaerobically digested at a mesophilic temperature of 37 °C and at a speed of 100 rpm for 15 days. The biogas produced was measured daily by using water displacement method. The total production of biogas for treated anaerobic digestion was 198.70 mL, meanwhile for untreated anaerobic digestion was 185.50 mL. Treated anaerobic digestion showed a slightly higher production of biogas in 15 days by 13.2 mL. The biogas yield obtained for treated and untreated anaerobic digestion was 51.21 mL/g and 47.80 mL/g for every 1 g of total wet sample. This study found that thermal treatment of anaerobic digestion helps in the degradation of organic content in food waste for anaerobic digestion, which leads to higher biogas recovery.
Mineral carbonation for carbon dioxide capture and storage using mining waste as feedstock material
Authors: Molahid V L M , Kusin F M , Soomro M H
Published: July 2023

Mineral carbonation can be a useful method for sequestering atmospheric carbon dioxide. This study attempts to evaluate the utilization of mining waste as a feedstock for mineral carbonation. Samples of mining waste have been analyzed for their mineralogical and chemical composition, and the amount of potential carbon sequestration was estimated. Mineralogical analysis suggests that the mine waste is composed of Ca-Mg-silicates (anorthite, wollastonite, diopside) and Fe-oxide (hematite and magnetite) minerals, which can be useful for mineral carbonation. Fe2O3 constituted a large portion of oxide compound (39.52-62.94%), with 7.19-15.24% CaO, and 0.10-9.58% MgO. Fe and Ca carbonation efficiency was estimated to be in the range of 4.04-6.45% and 2.38-6.31%, respectively. This corresponds to 60.94-155.44 g FeCO3/kg sample and 63.99-156.04 g CaCO3/kg sample, which can be sequestered from the mine waste. The total amount of CO2 sequestration is between 12.27-44.92 g of CO2 per kg of sample. Therefore, it has been shown that the method has successfully sequestered carbon dioxide into a stable carbonate form that can be stored for the long term. Application of this technology would be useful for reducing the amount of waste generated in the mining industry while mitigating the issue of carbon emissions.
Evaluation of irrigation water quality for paddy cultivation in Bachok, Kelantan
Authors: Norlida M H , Mohamad Shahid S , Jamaliah J , Muhamad Zamir AR , Hasliana K
Published: July 2023

Evaluation of irrigation water quality status was conducted in Bachok district, Kemubu Agriculture Development Authority (KADA) from July 2021 to March 2022. Water quality changes in the irrigation canal were examined by measuring several physical and chemical water quality at eight sampling points. The sampling locations are primary irrigation canals used to supply water into the paddy fields. Water quality parameter measured were temperature, pH, Dissolved Oxygen (DO), Conductivity, Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Suspended Solids (TSS), Ammoniacal Nitrogen (AN), Ca, Na and Mg. This paper aims to discuss irrigation water quality status using Water Quality Index (WQI), National Water Quality Standards (NWQS) and Sodium Adsorption Ratio (SAR). The results revealed that water quality were within NWQS Class II-IV except DO, AN and TSS in locations with intensive aquaculture. The average Water Quality Index in all sampling points ranged from 66.67-88.18, indicating that all irrigation water samples falls into the category of excellent and adequate water. The SAR values varied from 1.66-10.20, which means that all irrigation water samples were categorized into suitable for irrigation purposes. This work will help the decision makers to better manage irrigation water resources and policy development for paddy cultivation in KADA.
An alternative flood measurement approach: Flood Meter
Authors: Osman M S M , Rizal A I S , Zaini A Z W A , Kadir M A A , Kaamin M
Published: July 2023

Flash floods commonly occur in urban areas due to a short period of heavy rainfall associated with the large impervious area and inadequate drainage system. An increase in the uncertainty of predicting flash floods, especially due to climate change, reduces the accuracy of the existing flood forecasting system. In such cases, the affected zone’s actual flood level data is required for more effective flood management and incident response. This study aims to develop a mobile application called Flood Meter to identify flood levels in real-time. It measured the flood level based on object scale and images taken by mobile phones. Although the validation using an actual flood event with three different types of mobile phones shows lack of accuracy but by considered the maximum flood level only 0.17 m and the result keep improving when flood level increase, it shows a potentially good agreement compared with manual measurement. The application can become an alternative method to disseminate accurate real-time flood situations as well as flood data collection for future flood risk management.
Preliminary study on saltwater distribution of lowland area at West Coast, Johor Malaysia
Authors: Ismail Nor Suhaila , Musa Sabariah
Published: July 2023

Saltwater intrusion is a severe concern in coastal locations that pose a threat to the groundwater environment. Climate change, tidal effects, and groundwater exploitation all have the potential to disrupt the balance of salt water and fresh water in coastal aquifers which is the result of seawater intrusion that included the studies area. The sea-level rise is regarded as a cause that can enhance saltwater interface inland migration. Therefore, the purpose of this study is to assess saltwater intrusion in a zone mapping through the open channel distribution. This is qualified for monitoring a saltwater intrusion around West Johor which is approximately 10 km especially Batu Pahat, Johor such as Parit Botak, Parit Hailam Laut, Kampung Bahru Laut, Kampung Sri Pantai, and Sungai Senggarang. The salinity parameter was measured by the refractometer salinity instruments in percentage units (ppt) to PSU units. The high and low tides data collection on-site was monitored and analyzed saltwater intrusion distributed data into the interface mapping by using ArcGis 10.8 software. As the result, Kampung Sri Pantai was the highest data in the saline test 3 PSU for high tides and 4 PSU for low tides. However, the saltwater intrusion mapping was distributed through saline data obtained from the display maps to monitor the value of saline water in the study area. The contribution of this study to the community can be maintaining the ecosystem and monitoring existing structures such as tidal water gates and bunds of clean water resources for communities and irrigation purposes.
Discrepancies in estimated flood losses on paddy production: Application of damage models on historical flood records of the Northwest States of Peninsular Malaysia
Authors: Rehan B M , Yiwen Mok
Published: July 2023

Information of flood damage to crops production is essential for guiding risk-based decisions in reducing future adverse impacts of floods. For paddy, its susceptibility to floods is one of the factors that may influence the loss of paddy’s production. To date, there have been limited studies that have been undertaken to examine in detail how different damage functions (with and without a susceptibility index) influence flood damage estimates of paddy using past recorded flood information. This study attempts to examine flood damage functions of different forms in two conditions: as their stand-alone forms and when being applied for damage and risk estimations. Furthermore, recorded revenues from the past were used to investigate the effects of paddy’s susceptibility to floods on revenues. Historical flood evidence and revenues between 1987 and 2021 occurred on paddy granaries under the Muda Agricultural Development Authority’s (MADA) monitoring located in Perlis and Kedah states of Peninsular Malaysia and were used in this study. Application of three damage functions reveals that the exclusion of susceptibility index from the damage calculation results in significantly overestimations of losses, with a standard deviation reaching as high as 38 and overestimations up to four times that of the function with susceptibility index. The high estimates could hinder the acceptance of risk-based flood assessment (and its results) in flood alleviation decision-making. Furthermore, as the percentage of flooded area increases, the revenue loss increases, indicating the effects of floods on harvested paddy quality. This further highlights the potential role of the susceptibility index in the damage function.
Biohydrogen production from kitchen organic waste via effective pre-treatment process of dark fermentation
Authors: Jais F K A , Hassan S H A , Zamri M F M A , Zulkornain M F , Shamsuddin A H
Published: July 2023

This research aims to highlight the effective pre-treatment process for biohydrogen production from kitchen organic waste in dark fermentation. The complexity of the fermentation process through the competing of the metabolic living bacteria requires a dynamical control of the process through the pre-treatment of the substrate’s mixtures. In this research the pre-treatment process parameters and inoculum condition that affect biohydrogen production via dark fermentation process were investigated. The parameter that affects biohydrogen production via the dark fermentation process have also been analysed. The performance of two inoculums from food waste and cow manure were tested with three different pre-treatment processes: thermal, acid and alkaline. Based on the results, the cow manure inoculum was the best-performing inoculum, producing more H2 compared to food waste inoculum. Furthermore, the substrate and inoculum with thermal shock pre-treatment approaches has increased the biohydrogen generation compared to acid and alkaline pre-treatment.
Bioremediation of fibreboard sludge by using bacteria and fungi
Authors: Kadapi Intan Nursyazwani Makmar , Rais Nurul Nasuha Mohd , Kamil Nor Amani Filzah Mohd , Alias Salina
Published: July 2023

Sludge produced from the fibreboard industry releases hazardous substances that may damage the environment as well as human health via inhaled air, drinking water, and food consumed. Correspondingly, the aim of this study was to focus on the bioremediation to treat industrial wastewater sludge produced from Evergreen Fibreboard, Parit Raja, Batu Pahat, Johor by using bacteria (Sphingobacterium spiritivorum) and fungi (Aspergillus brasiliensis). Three stages of the investigation were performed, which are the collection of raw materials, the preparation of microbes, and sample analysis, including the determination of COD and heavy metals including Chromium (Cr), Copper (Cu), Arsenic (As), Lead (Pb) and Zink (Zn). From the Chemical Oxygen Demand (COD) test, Aspergillus brasiliensis shows higher potential for sludge bioremediation as 61 mg/L COD was reduced in 14 days compared to the Sphingobacterium spiritivorum which only 31 mg/L was reduced. Meanwhile, the leaching result for heavy metals shows that Zn had the highest concentrations and As was the lowest for 14 and 28 days. Inoculation of Aspergillus brasiliensis shows the lowest leaching concentration for heavy metal elements such as Cr, Cu, As, Pb and Zn compared to Sphingobacterium spiritivorum. The reduction concentrations of these elements are 13%, 22%, 17%, 33% and 6%, respectively. The result shows that the fungi strain has the highest capability to absorb metals compared to the bacteria strain. Indigenous microorganisms in sludge have the lowest potential to reduce COD and heavy metals. However, a combination with the other method such as physical and chemical processes would be recommended to improve the results in the future.
Effects of treatment for raw oil palm shell on compressive strength of oil palm shell concrete
Authors: Ng D C P , Lau T L , Anwar M P , Elleithy W , Hama M F
Published: July 2023

This paper presents test results of thirty-two OPSC (Oil Palm Shell Concrete) cubes cast with OPS (Oil Palm Shell) under different treatment condition and with different cement content. The study concludes that OPSC cast using fully treated (Wash-Dry-Sieve) OPS yields the highest compressive strength, an increase of 65% in comparison with using untreated OPS. The increase in strength can be attributed to 1) Removal of residual oil on OPS surface via washing with detergent, mass 2% of the dry OPS mass, and 2) Removal of sub-2mm particles in OPS via sieving comprising of soil and OPS fibres. OPSC can develop compressive strength at a higher rate with washing, drying and sieving treatment performed on OPS compared with concrete cast with untreated OPS.
Sustainable facilities management in Malaysia: Adoption challenges and the way-forward for improvements
Authors: Moayedi Farzaneh , Klufallah Mustafa , Tanko Bruno , Hasmori Fikri , Khit Simon
Published: July 2023

One of the most important issues the world is currently facing is climate change. The sustainability agenda needs to be incorporated into the built environment in order to address this issue. Facilities management (FM) is regarded as having the greatest potential to drive and incorporate the sustainability agenda into the built environment. There can be a significant environmental impact from FM services provided in buildings. This resulted in the combination of FM activities and sustainability principles, giving rise to the idea of sustainable facilities management (SFM). In the context of Malaysia, this paper identifies the issues with SFM and potential solutions. The research used a quantitative approach to gather data through a questionnaire survey, and the Relative Importance Index (RII) was used for data analysis. The results show that, energy consumption reduction is the widely implemented practice, while legislation is the most important driver of SFM in Malaysia. Financial constraints and a lack of knowledge and understanding of SFM are the least significant barriers to SFM implementation. Participation in SFM workshops or training is the most crucial improvement that should be made, while investing in building information modelling or other pertinent technologies for FM purposes is the least crucial improvement. Overall, the results show that Malaysia’s rate of SFM adoption and implementation is still low.
Physical properties of Dolomite fines as partially replacement of cement
Authors: Rahim Mustaqqim Abdul , Ivin Chan , Ibrahim Norlia Mohamad , Shahidan Shahiron , Ayob Afizah , Bawadi Nor Faizah , Anudai@Anuar Shamilah , Zuki Sharifah Salwa Mohd , Salehuddin Shamshinar
Published: July 2023

Since the cost of cement increases and the pollution to environment due to greenhouse effect are becoming more serious year by year, thus, dolomite fines subjected to replace the cement in concrete mix as it has lower cost compared to cement and it is obtain directly from the Earth ground without any manufactured process. Dolomite fines also shows almost similar physical and chemical properties as cement. The various replacement of cement with dolomite fines carried out in this study is 0%, 5%, 10%, 15% and 25%. The grade of concrete sample designed to be 30. The properties of concrete sample in terms of physical characteristics; slump, density and water absorption for various percentage replacement are determined in this study. In this study, it shows the dolomite fines are lightweight aggregate compared to the cement and the water absorption of is lower compare to that of the control concrete.
Combination of Rice Husk Ash (RHA) and Sewage Sludge Ash (SSA) as sustainable replacement material for cement in concrete
Authors: Tutur Nuraini , Daud Nurhidayati Mat , Rosseli Siti Rahimah , Yunus Juzailah Nur , Abdullah Mohd Fazli
Published: July 2023

Increase in the demand of conventional construction materials and the need for providing a sustainable growth in the construction field has prompted the designers and developers to opt for ‘alternative materials’ feasible for use in construction. For this objective, the use of industrial waste products and agricultural by products are very constructive. These industrial wastes and agricultural by products such as Rice Husk Ash and Sewage Sludge Ash can be replaced instead of cement because of their pozzolanic behaviour, which otherwise requires large tract of lands for dumping. In the present investigation, Rice Husk Ash has been used as an admixture to cement in concrete and its properties has been studied. An attempt was also done to examine the strength and workability parameters of concrete. Five different replacement levels namely 5%, 10%, 15%, 20% and 25% are selected and studied with respect to the replacement method. The samples had been tested with non-destructive test to compare with normal concrete (OPC). There was an increment in number of concretes at 10% amount replacement SSA and RHA, but the rebound number declined when the amount replacement SSA and RHA are developing more than 10%. In addition, the concrete also showed increasing of compressive strength within the additional curing period, which was 7 days and 28 days. The overall results indicated that the properties and performance of concrete with 10% of combination of Rice Husk Ash (RHA) and Sewage Sludge Ash (SSA) replacement had reached the most optimum values on the measured.
Development of Graphene Oxide/Polyethylene to enhance mechanical properties through melt mixing technique
Authors: Yusof M A , Nor Rahman N H , Izirwan I , Mat Desa M S Z , Ab Ghani N F
Published: July 2023

Graphene Oxide (GO) was added to Low-Density Polyethylene (LDPE) to test the mechanical properties of the compound. Compared to other types of polyethylene, LDPE provides a good balance of mechanical properties and processability, which leads to its being chosen as the research’s matrix material. This experiment aims to prepare LDPE/GO through melt mixing technique and analyse mechanical properties of tensile strength/tensile elongation of LDPE/GO composite based on GO concentration (0, 0.5, 1.0 and 1.5 wt%). The compounding of LDPE/GO was blended using a five-stage twin-screw extruder under specific conditions before going through the moulding process at melting temperature. The composites were cut according to ASTM D638 specimen dimension. The tensile properties of LDPE composites were filled separately with different weight fractions of GO at a 50 mm/min rate. It was found that the values of Young’s modulus of the composites increased, but the values of the tensile elongation at break decreased with increasing the GO weight fraction. The relatively big interfacial area and excellent interfacial adhesion between the matrix and the GO may be responsible for the composites’ reinforcement. This study provided a basis for further development of GO-reinforced LDPE composites with desirable mechanical performance and good damage behaviour.
The contribution of green building in reducing the carbon footprint and attaining SDG 13
Authors: Ahram F H , Zakaria Sh A Syed
Published: July 2023

As a result of the construction industry’s rapid growth, several local and international environmental issues have developed in recent years. Thus, numerous new environmental programs have been formed worldwide with the goal of reducing CO2 emissions and attaining the Sustainable Development Goals (SDGs). Therefore, the built environment must play an important role in keeping up with this development. Based on in-depth interviews with 15 experts in the field of green buildings in Jordan, this study aims to examine the role of green building technology (GBT) in Jordan in lowering CO2 emissions and achieving SDG13, which calls for taking urgent action to combat climate change and its impacts. The findings from this paper reveal that there is a strong relationship between the implementation of GBT and the lowering of CO2 emissions resulting from the construction industry in Jordan, which contributes to achieving SDG13. The significance of this paper is to develop the basis of understanding of the importance of GBT adoption for further explorations and studies as an important field for the built environment in achieving the SDGs, which serve as a crucial foundation in protecting our planet and preserving the environment for future generations.
Ranking the critical causes of accidents in construction projects of Sindh: Perspective of safety professionals
Authors: Memon M H , Abas N H , Sohu S
Published: July 2023

Construction projects are running very rapidly throughout the world and undergoing many challenges like delay, quality standards, cost overruns, and accidents. Accidents at workplace have been a very common issue nowadays particularly in construction projects. The objective of this paper is to identify and rank the critical causes of accidents in building construction projects. The area of work is in the province of Sindh in Pakistan. For this study, the quantitative research methodology was used, and a questionnaire survey was conducted among safety professionals working on construction projects in Sindh. The average index method was used to analyse the data collected from the questionnaire survey. This study has determined a total of seven main causes of accidents in building construction projects, such as no edge protection; no availability or poor quality of personal protective equipment; violations of safety rules and regulations; carelessness or negligence; extensive subcontracting and outsourcing; malfunctioning or collapsing equipment or machinery, and a compressed work program. This research highlighted the critical causes of accidents in building construction projects and assisted the stakeholders of the construction industry in narrowing down some of the critical causes. Moreover, the results of this study motivate construction stakeholders to concentrate on the problems of accidents in building projects in Sindh.
Application and development of Artificial Neural Networks to predict structural damage subjected to earthquake-A review
Authors: Hakim S J S , Panguot D , Kamarudin A F , Chik T N T , Ghafar N H A , Yusoff N A , Tong Y G
Published: July 2023

The complexity of earthquake incidents supports efforts to use machine learning methods as an alternative to conventional methods because they can simply capture difficult relations between the input and output parameters without requiring a particular functional structure. Machine learning is a branch of artificial intelligence techniques that applies the capacity of machines to recreate intelligent human behavior and has been receiving increasing consideration as an effective solution for damage detection due to earthquakes. Artificial neural networks (ANNs) are one of the most important machine techniques, inspired by the human brain. There hasn’t been a lot of published research on the use of ANNs for structural damage identification to predict earthquakes on various structures up until now. This paper presents a comprehensive review of recent studies on the applications and development of ANNs to predict earthquakes and damage caused by earthquakes on different structures. ANNs can learn from their experience and have drawn significant consideration in damage detection due to their capability of pattern identification and error tolerance in forming a nonlinear modeling between the inputs and outputs. According to this research, the use of ANNs can prevent unpredictable failures and reduce maintenance costs, increasing the safety and functionality of structures. A brief introduction to the ANN algorithm is presented first. Following that, the benefits, and limitations of ANNs, as well as some new research trends, have been discussed.
The benefits and application of green concrete towards sustainable built environment: A case study within Kuala Selangor area
Authors: Yahya Nik Fatma Arisya Nik , Sunarti Noorhidayah , Hin Loh Ja , Mahdzir Mazura , Mohamed Nik Norzahariah Ashikin N.
Published: July 2023

Environmental issues have become a global concern as it is getting serious and worse which eventually brings unforeseeable destructive impacts. The construction industry is regarded as one of the main contributors to this issue. Concrete that is used in construction is known as one of the most widely used materials on the earth, which on the other hand, poses a significant environmental issue. About 8 – 10% of carbon dioxide emissions are generated by the cement industry. In addition, greenhouse gases are released to the environment when natural aggregates are crushed and heated at elevated temperatures, which directly intensifies environmental burdens. To tackle the issue from the fundamental aspect, green concrete is introduced into the Malaysian construction industry. With an aim to promote green concrete application in the construction industry, this paper will achieve two objectives which include (i) to identify the benefits of green concrete to the environment (ii) to discuss the application of green concrete in construction projects. The primary data collection involves 87 sets of questionnaire survey which is distributed to the contractor’s company. The research findings revealed the benefits of green concrete (i.e., reducing waste, reducing greenhouse gas emissions, and conserving natural resources) and it was found only 24 respondents are having experience in green concrete application.
Rapid visual assessment of crack on residential building
Authors: Chik T N T , Jalil A. A. M. , Yusoff N A , Hakim S J S , Ghafar N H A
Published: July 2023

Crack is a form of defect that mainly seen in any types of building including residential buildings. Building crack-free is unrealistic as the crack cannot be fully prevented during the construction process. However, the crack cannot be simply taken only as visually unattractive, it is also having a major effect on structure safety. This is because the crack does not pose a direct threat to building safety but it does encourage certain behaviours that can lead to serious safety issues. Even though the crack presence cannot be nullified, the crack can be prevented before becoming wider and worst. Therefore, crack assessment is very important. This study is focusing on the evaluation of cracks in residential buildings at Ayer Hitam, Muar, Johor. The main objective of this study is to assess the visual cracks rapidly on residential buildings in terms of crack width and their direction either horizontal, vertical, diagonal, or stair-step. The second objective is to determine the severity and location of cracks on wall surfaces of residential buildings. As a results, Site 1 has the biggest crack width of 21mm located at the kitchen wall and is classified as a severe crack. Meanwhile at Site 2, the biggest crack width is 6mm and classified as a moderate crack. The crack was spotted on the right-side wall of the house. Apart from that, the types of cracks recorded at both sites are vertical, diagonal, and horizontal. As a conclusion, the causes of crack were investigated. Soil settlement is might be the main factor of cracks happened at both sites due to peat soil type at both locations.