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The renewed interest for power generation using renewables due to global trends provides an opportunity to rethink the approach to address the old yet existing load shedding problem. In the literature, limited studies are available that address the load shedding problem using a hybrid renewable energy system. This paper aims to fill this gap by proposing a techno-economic optimisation of a hybrid renewable energy system to mitigate the effect of load shedding at the distribution level. The proposed system in this work is configured using a photovoltaic array, wind turbines, an energy storage unit (of batteries), and a diesel generator system. The proposed system is equipped with a rule-based energy management scheme to ensure efficient utilisation and scheduling of the sources. The sizes of the photovoltaic array, wind turbine unit, and the batteries are optimised via the grasshopper optimisation algorithm based on the multi-criterion decision that includes loss of power supply probability, levelised cost of electricity, and payback period. The results for the actual case study in Quetta, Pakistan, show that the optimum sizes of the photovoltaic array, wind turbines, and the batteries are 35.75 kW, 10 kW, and 28.8 kWh, respectively. The sizes are based on the minimum values of levelised cost of electricity (6.64 cents/kWh), loss of power supply probability (0.0092), and payback period (7.4 years). These results are compared with conventional methods (generators, uninterruptible power supply, and a combined system of generator and uninterruptible power supply system) commonly used to deal with the load shedding problem. The results show that the renewable based hybrid system is a reliable and cost-effective option to address grid intermittency problem.

Old landfill leachate is normally rich in colloidal particles, has low organic compound, poor biodegradability and hard to be biologically treated. The suspended particles are generally dispersed, ...

An early and reliable estimation of crop yield is essential in quantitative and financial evaluation at the field level for determining strategic plans in agricultural commodities for import-export policies and doubling farmer’s incomes. Crop yield predictions are carried out to estimate higher crop yield through the use of machine learning algorithms which are one of the challenging issues in the agricultural sector. Due to this developing significance of crop yield prediction, this article provides an exhaustive review on the use of machine learning algorithms to predict crop yield with special emphasis on palm oil yield prediction. Initially, the current status of palm oil yield around the world is presented, along with a brief discussion on the overview of widely used features and prediction algorithms. Then, the critical evaluation of the state-of-the-art machine learning-based crop yield prediction, machine learning application in the palm oil industry and comparative analysis of related studies are presented. Consequently, a detailed study of the advantages and difficulties related to machine learning-based crop yield prediction and proper identification of current and future challenges to the agricultural industry is presented. The potential solutions are additionally prescribed in order to alleviate existing problems in crop yield prediction. Since one of the major objectives of this study is to explore the future perspectives of machine learning-based palm oil yield prediction, the areas including application of remote sensing, plant’s growth and disease recognition, mapping and tree counting, optimum features and algorithms have been broadly discussed. Finally, a prospective architecture of machine learning-based palm oil yield prediction has been proposed based on the critical evaluation of existing related studies. This technology will fulfill its promise by performing new research challenges in the analysis of crop yield prediction and the development of an extremely effective model for the prediction of palm oil yields with the most minimal computational difficulty.

This is an era where the application of adsorption and usage of activated carbons (AC) are considered as mainstream water treatments. The upgrade of these materials may only be through its preparation methods, where most researchers have transitioned from using the conventional furnace methods to using microwave ovens. Derived from various precursors, ACs can be the key in developing numerous environmental applications. This paper reviews the development of production processes of AC from various precursors in the past decades by microwave heating. The importance of the applied methodology and how activating conditions play an influential role, such as carbonisation temperature, activation time, and impregnation ratio are also outlined in this review. From the review of AC production processes, ACs produced from various precursors by chemical method with microwave heating have shown to be the significant factor in developing ACs with relatively higher surface area compared to conventional heating ACs.

Old leachate normally has a low organic compound content, poor biodegradability and is hard to biologically treat. The efficacy of tetravalent metal salts as a coagulant and the application of a natural coagulant as a flocculant in landfill leachate treatment is still inconclusive. Hence, this study aimed to evaluate the potential application of tin tetrachloride (SnCl4) as the main coagulant and the rubber seed (Hevea brasiliensis) (RS) as the natural coagulant aid as the sole treatment in eradicating highly coloured and turbid stabilised landfill leachate present at one of the old local landfills in Malaysia. The standard jar test conducted revealed that SnCl4 was able to eliminate 99% and 97.3% of suspended solids (SS) and colour, respectively, at pH8, with 10,000 mg/L dosages, an average particle size of 2419 d·nm, and a zeta potential (ZP) of −0.4 mV. However, RS was found to be ineffective as the main coagulant and could only remove 46.7% of SS and 76.5% of colour at pH3 with 6000 mg/L dosages, and also exhibited smaller particles (933 d·nm) with ZP values of −6.3 mV. When used as a coagulant aid, the polymer bridging mechanism in RS helped in reducing the SnCl4 concentration from 10,000 mg/L to 8000 mg/L by maintaining the same performances. The presence of 1000 mg/L RS as a coagulant aid was able to remove 100% of SS and 97.6% of colour. The study concluded that RS has the potential to be used together with SnCl4 in treating concentrated leachate with SS and colour.

Dam reliability analysis is performed to determine the structural integrity of dams and, hence, to prevent dam failure. The Chenderoh Dam structure is divided into five parts: the left bank, right bank, spillway, intake section, and bottom outlet, with each element performing standalone functions to maintain the overall Dam’s continuous operation. This study presents a numerical reliability analysis of water dam reservoir banks using fluid–structure interaction (FSI) simulation of the bottom outlet structures operated at different discharge conditions. Three-dimensional computer-aided drawings were used to view the overall Chenderoh Dam. Next, a two-way fluid–structure interaction (FSI) model was developed to explore the influence of fluid flow and structural deformation on dam systems. The FSI modeling consists of Ansys Fluent and Ansys Structural modules to consider the boundary conditions separately. The reliability and performance of the reservoir bottom outlet structure was effectively simulated and recognised using FSI. The maximum stress on the bottom outlet section is 18.4 MPa, which is lower than the yield stress of mild steel of 370 MPa. Therefore, there will be no structural failure being observed on the bottom outlet section when the butterfly valve is fully closed. With a few exceptions, the FSI models projected that bottom outlet structures would be able to run under specified conditions without structural collapse or requiring interventions due to having lower stress than the material’s yield strength.

Recently, the contribution of earthworms to plastic degradation and their capability to swallow smaller plastic fragments, known as microplastics, has been emphasized. The worm physically changes the size of microplastics and enhances microbial activities to increase the possibility of degradation. However, no research has shown that earthworms can chemically degrade microplastics to an element form, CO2 or H2O. In this review, previous research has been thoroughly explored to analyse the role that earthworms could play in plastic degradation in the soil. Earthworms can significantly affect the physical characteristics of plastics. However, earthworms’ abilities to chemically degrade or change the chemical structure of plastics and microplastics have not been observed. Additionally, earthworms exhibit selective feeding behaviour, avoiding areas containing a high plastics concentration and rejecting plastics. Consequently, earthworms’ abilities to adapt to the microplastics in soil in the environment can cause a problem. Based on this review, the challenges faced in earthworm application for plastic degradation are mostly expected to be associated with the toxicity and complexity of the plastic material and environmental factors, such as the moisture content of the soil and its temperature, microbial population, and feeding method.

This work examines standard Urdu text to confirm impact of word order in the language structure. The complex network approach is used to obtain universal properties of two different word co-occurrence networks. Macro and micro scale two-fold examinations of networks are performed for structure discovery. While preserving the vocabulary size, two networks are generated from same text with and without standard word order. In addition, text networks are benchmarked with a random network to extract global features. Achieved outcomes indicate certain word order in Urdu structure for most of the sentences. The normal and shuffled text networks demonstrated similar large-scale characteristics. The results show that average path length and network diameter is reduced after shuffling. On the other hand, clustering coefficient is increased in shuffled text as compared to normal text. Our results validated that few short sentences in range of three words are fully free order. The observations revealed that long sentences are ambiguous without standard order. Both networks are topologically similar but shuffling caused massive discrepancy in network composition and sentence structure. Inside graph view, grammatical association-based words connectivity exists in normal text network. With this universal approach, impact of word order in Urdu language is confirmed. Meanwhile, this breakthrough directs to uncover language composition by extracting small sentences as motifs.

Coffee is globally the second largest most traded commodity after petroleum, and this has facilitated many countries to grow and produce coffee in commercial quantity. The production processes uses large volume of water which comes out as contaminated water. The presence of toxic chemicals like tannins, phenolic and alkaloids inhibits biological degradation. Microbial processes break down the organic substances released into water bodies slowly, using up the oxygen from the water (COD). As demand for oxygen needed to break down organic waste in a wastewater begins to exceed supply, a decrease in oxygen needed to combine with chemicals (COD) slowly creates anaerobic condition. The review looks at few of the current methods (physicochemical and biological) used in coffee wastewater management, their advantages and disadvantages including, high cost implication, complex operation and more time consumption among others; furthermore, the review suggests ion exchange technique as a better alternative based on its capacity to act as both an ion exchanger and absorber.

The uptake of polylactic acid (PLA) microplastics, the most commonly used biodegradable plastics by earthworms Eudrilus eugeniae was investigated by observing their weight changes, biomass and the microplastics concentration after feeding them with a mixture of PLA and cow dung for 16 days at the concentrations of 0%, 10%, 30%, 60%, and 80% w/w dry weight. The mortality rate of the earthworms for all the PLA concentrations during the 16 days of feeding period was 0%. However, the microplastic affected the earthworms' weight significantly (P-value 0.00027), especially at the concentration of 80% of PLA. The earthworms had the lowest weight gain at 80%, followed by 60%, 30%, and 10% of PLA, respectively. The earthworms subjected to 80% and 10% of PLA had a similar pattern with the control. This was perhaps due to the high organic matter in the worm’s feed for the 10% PLA and the digestion mechanisms, which led the earthworms to preserve their energy and become less active in the 80% PLA, compared to all the other treatments. The PLA microplastics concentration factor (CF) in the vermicast was the highest at the 10 % PLA compared to other treatments, because Eudrilus eugeniae did not degrade the PLA. This study concludes that even though PLA is a biopolymer-based, it cannot be bio- assimilated by the earthworm.

This study assesses the structural analysis on the sector gate in dam spillway with 5 m gap opening. The parameters determined on this study are equivalent stress and total deformation. The structure analysis on the spillway structure is due to the impact of water discharge. Computational fluid dynamic (CFD) modelling is applied to assess the water flow that affect stress and deformation occurred using computational aided program using ANSYS. Result of the transient structure model show that the highest stress value is at the radial gate which is 29.69 MPa and the lowest stress value is at stilling basin which is 0.037 x 10−9 MPa. All the deformation values are relatively low especially at the stilling basin which is 1.021 x 10−9 m and the largest deformation value is at the radial gate which is 10.47 x 10-6 m. It can be concluded that the stress and deformation give different result due to different materials. Stress and deformation values at mild steel material parts are higher than concrete material parts due to the high impact of water pressure. Future mitigation measures have to take to ensure the sustainability of the structural integrity.

Machine learning (ML) offers new technologies in the precision agriculture domain with its intelligent algorithms and strong computation. Oil palm is one of the rich crops that is also emerging with modern technologies to meet global sustainability standards. This article presents a comprehensive review of research dedicated to the application of ML in the oil palm agricultural industry over the last decade (2011–2020). A systematic review was structured to answer seven predefined research questions by analysing 61 papers after applying exclusion criteria. The works analysed were categorized into two main groups: (1) regression analysis used to predict fruit yield, harvest time, oil yield, and seasonal impacts and (2) classification techniques to classify trees, fruit, disease levels, canopy, and land. Based on defined research questions, investigation of the reviewed literature included yearly distribution and geographical distribution of articles, highly adopted algorithms, input data, used features, and model performance evaluation criteria. Detailed quantitative–qualitative investigations have revealed that ML is still underutilised for predictive analysis of oil palm. However, smart systems integrated with machine vision and artificial intelligence are evolving to reform oil palm agri-business. This article offers an opportunity to understand the significance of ML in the oil palm agricultural industry and provides a roadmap for future research in this domain.

In wastewater treatment field, physicochemical techniques containing conservative substance such as metal or substance that are non-biodegradable are typically employed. However, these techniques have their own drawbacks and none of them is universal in treating all kinds of metal present in the wastewater. Separation procedure is known to be very suitable for the separation and recovery of metal ions. The solvent extraction or liquid–liquid extraction, LLE, was opted in this study to identify the influencing factors on the extraction of cadmium(II) and copper(II) ions from aqueous solution by using soybean-based oil as organic solvent. The experiment was approached using fractional factorial design to determine the significance of six factors which are concentration of di-2-ethylhexylphosphoric acid (D2EHPA), concentration of tributyl phosphate (TBP), shaking time, the concentration of Na2SO4, O/A phase ratio and aqueous pH. The results have shown that %E shows that Cu(II) was obtained in the range from 35.77 to 91.81%, while the result obtained from the factorial plot of screening experiment shows that the interaction effect AB (shaking time × [D2EHPA]), CE ([TBP] × O/A) and DF ([Na2SO4] × pH) influences significantly the Cu(II) %E. Meanwhile, %E for a sample containing Cd(II) ion was obtained in a range from 54.77 to 87.35%.

In recent years, oil and grease has been identified as an emerging pollutant of concern (EPC) in wastewater stream as it can disturb the ecology and wastewater treatment process efficiency. The highest contributor to oily wastewater among domestic wastewater is from kitchen greywater. One of the alternatives to address this problem is the application of enzyme. The production of enzyme by using organic waste has gained significant attention in the recent years due to sustainable demand from it. In this study, pectinolytic enzyme was produced through simplified fermentation from discarded citrus peels that possess high lipase content. Three batches of treatment which consist of the control sample (solely wastewater), 25% (v/v) citrus enzyme + wastewater and 50% (v/v) citrus enzyme + wastewater was incubated in an incubator shaker for 10 days at 30 °C and 150 rpm. The wastewater analysis was performed at a regular interval of 48 h. The parameters monitored were pH, BOD5 and oil and grease. Laboratory work has demonstrated that 25% (v/v) pectinolytic enzyme was able to remove BOD5 and oil and grease about 10% better than 50% (v/v) pectinolytic enzyme. The percentage of removal achieved by 25% (v/v) pectinolytic enzyme was 39.83 ± 9.50 mg/L and 64.21 ± 1.12 mg/L, respectively. However, it was observed that enzyme was less effective in removing BOD5 as the solution contains organic matter that increases the total organic matter in the wastewater mixture.

Sanitary landfilling is the most acceptable method to eliminate solid urban wastes. However, it is known that sanitary landfill generates large amount of heavily polluted leachate. High concentrations of recalcitrant organics make its degradation more complicated and high concentration of organic material can be toxic and reduce bioremediation process. Landfill leachate treatment by advanced oxidation processes (AOPs) have been intensively studied with high successful rate for removing refractory pollutants (biological degradation) from leachate. Fenton reaction which is one basic AOPs is based on the addition of hydrogen peroxide to the leachate in the presence of ferrous salt as a catalyst. Because of that, many improvement and development of new Fenton-based methods have been reported in the literature. This review discussed the application of Fenton and related processes in terms of wide application in landfill leachate treatment. The effects of various operating parameters and their optimum ranges for organics contaminant removed were also discussed.

The purpose of this paper is to present examples of independent water and wastewater treatment methods in a way to provide clean water to the community. Out there, tons of method exists to reduce the effect of the water pollutant and improve the water quality problems. In order to reduce the water problems, this paper focuses on the process of water and wastewater treatment by using three different methods which are natural and independent water and wastewater treatment, independent artificial water, and wastewater treatment and hybrid water and wastewater treatment. Natural independent method mostly using vegetation as a medium or mechanism to purify water. For the hybrid method, green energy artificial floating island(GAFI), solar power artificial floating Island (SAFI) and solar power lake and pond aeration system were studied the removal efficiency by all the devices. The methods were reviewed in order to find the efficiencies and effectiveness of each method.

This study investigated the effectiveness of batch electrocoagulation with vibration-induced electrode plates in enhancing the role of gas bubbles in the removal of ammoniacal nitrogen (NH3-N) from landfill leachate. The experimental setup, which consisted of an electrocoagulation reactor and electrode plates attached to a vibrator motor and connected to a DC-power supply, was employed to determine the effects of the vibration intensity, initial pH, operating time and current intensity on the percentage removal of NH3-N. The results revealed that the removal of NH3-N was optimum when the plates vibrated at 2.8 V. Further analysis at this optimum vibration intensity showed that the percentage removal of NH3-N was enhanced at an initial pH of 10 for both the vibrating and stationary plates. While the treatment with stationary plates showed an increase in the percentage removal of NH3-N with time, an optimum time of 35 min was achieved for the treatment using the vibration-induced plates. The results showed that the higher the current intensity, the higher the removal of NH3-N. Electrocoagulation with both the stationary plates and vibration-induced plates was able to achieve 40% and 50% removal of NH3-N, respectively at a current intensity of 4.5 A. The percentage removal of NH3-N through electrocoagulation with the vibration-induced electrode plates was found to have improved compared with the use of stationary plates due to the better dispersion of gas bubbles, which reduced the attachment and accumulation of bubbles on the surface of the electrode plates, thereby enhancing the ionic transfer between the plates.

In most of electrocoagulation processes, the efficiency in removing pollutant is not just dependent on anode oxidation but is also determined by the action of gas bubbles produced during the treatment. The bubbles formation and bubbles rise velocities are important especially in electrochemical treatment for which generated gas bubbles improved the ionic transfer and dispersion of particles. This study used the Particle Image Velocimetry (PIV) technique to investigate the hydrodynamics of bubbles in terms of size, distribution and rise velocity in batch electrocoagulation with vibration-induced electrode plates in comparison with stationary plates. An experimental set up consisting of an electrocoagulation reactor and electrode plates equipped with a high-speed camera recorder and a computer embedded with PIVlab software was employed to determine the bubble sizes and the rise velocities in varying conditions, such as current intensity, initial pH, and vibration intensity. The results showed that, for both stationary and vibration-induced plates, smaller bubble sizes were obtained in acidic conditions (pH 5) compared with alkaline conditions (pH 10). The larger bubble sizes were found resulted from the coalescence between smaller and larger bubbles before detachment from the plates. However, due to the vibration of the plates, the bubbles were able to completely detach from the plate surfaces starting at a vibration intensity of 1.8 V. With stationary electrode plates, the bubble rise velocities were found to be higher at initial pH 5 with velocities ranging from 4.7 to 15.3 cm/s, while the velocities measured at initial pH 10 ranged from only 2 to 4.7 cm/s. The flow trajectory of the stationary plates showed that the bubbles flowed only in a single direction parallel to the plate (y-direction). On the other hand, increasing the vibration intensity of the vibration-induced plates from 0.8 to 3.3 V during the treatment resulted in a decrease in the bubble rise velocities at both initial pH 5 and pH 10. The gas bubbles flow was governed by both the x- and y-direction of the electrode plates, with the flow in the x-direction observable at a vibration intensity of 2.8 V or 80 Hz, which is the resonant frequency of the vibrating plates.

As an alternative of coagulant based aluminium (Al) in landfill leachate treatment, starch-based coagulants have been synthesised from Durio zibethinus seed starch (DSS) and studied for its potential as a natural coagulant and coagulant aid in the presence of PACl to remove organic matter and heavy metal using coagulation and flocculation process. Leachate sample was sampled from Larut Matang landfill, Perak, Malaysia. The optimum DSS dosage was 360 g/L at pH 9. The addition of DSS as a coagulant aid improved the removal rate of colour, turbidity and zinc. However, the addition of DSS as a coagulant aid increased the concentration of manganese by 15%. It was assumed that PACl was more superior than DSS for the removal of turbidity, colour, COD and iron removal. In conclusion, DSS has the potential to be a coagulant aid in coagulation and flocculation based on their removal efficiency values.

In electrocoagulation, the accumulation of gas bubbles surrounding the electrode plate surface results in high internal resistance between the electrode plates that obstruct optimum ionic transfer, subsequently reducing the electrocoagulation efficiency. This study investigated the performance of batch electrocoagulation designed with vibration-induced electrode plates in the treatment of landfill leachate to remove colour and chemical oxygen demand (COD). The electrode plates in the electrocoagulation cell were each attached with a DC motor vibrator, varied at different vibration intensity in which its effect on the initial pH, operating time and electrical current of the electrocoagulation were determined. The results showed that the application of vibration-induced electrode plates had a synergistic effect with the electrocoagulation with more than 90 % of colour and COD up to 35 % removed during the treatment at vibration intensity of 2.8 V, initial pH 5, operating time of 35 min, applied current of 2.5A (applied voltage ranged between 11.0–12.9 V), with calculated electrical energy consumption of 8.58 kW h/m3. Overall, the vibration-induced electrode plates were found to enhance the treatment performance due to a combination of improved ionic transfer, enhanced bubbles detachment from the electrode surface and dispersion in the solution. The detachment of bubbles from the plates also enable improved mixing in the solution, leading to an increase in homogeneity and better sludge separation following treatment. In conclusion, this study showed that electrocoagulation with vibration-induced electrode plates provided an improved technique in enhancing the ionic transfer and bubbles dispersion in electrocoagulation for the removal of pollutants.

Fluid dynamic field is frequently classified and designated into two which are hydrodynamics and aerodynamics. Particle Image Velocimetry (PIV) has been exerted to many flow problems in a broad range. PIV application to the measurement of velocity distributions in fluid flow is represented by the Stokes number. PIV can be executed to practically for any sort of flow if the fluid is transparent to allow suspended particles image. The purpose of this paper is to present some examples of application of PIV in general cases. In the midst of numerous applications of PIV, turbulent flows are the most comprehensively demanding because of their three-dimensionality, naturally large ranges of length and unsteadiness. Sudden flow field measurements of PIV method can be applied for the demotion of turbulence quantities and mean velocities.

The increasing consumption of fisheries product causes large amount of wastewater produced from fish processing industry. General wastewater treatment includes the use of harmful chemical such as chlorine. This research opens a new platform to treat wastewater by using ionic cupric copper which is also known as copper nanoparticles (CuNP). Copper nanoparticles are synthesized through chemical reduction method by using Copper sulphate pentahydrate (CuSO4.5H2O) as precursor and Sodium hydroxide (NaOH) as reducing agent. The physical characterizations of CuNP are carried out by using SEM and the chemical characterizations are carried out by using XRD and FTIR. The efficiency of CuNP to treat wastewater from fish processing industry are determined by the removal of COD, Total coliform and E.Coli. The optimum concentration to reduce COD is 1000mg/L which causes 59.4% percentage removal of COD. The optimum concentration for COD removal is used to determine the volume of CuNP needed to remove total coliform and E.Coli. The optimum volume for removal of total coliform and E.Coli are 40µL and 30 µL respectively.