Groundwater is the main source of water in the Kingdom of Saudi Arabia (KSA). A larger part of groundwater is founded in alluvial (unconfined) aquifers. Prediction of water table elevations in
unconfined aquifers is very useful in water resources planning and management. During the last two
decades, many aquifers in different regions of the KSA experienced significant groundwater decline.
The declines in these aquifers raised concerns over the quantity and quality of groundwater, as well
as concerns over the planning and management policies used in KSA. The main objective of this study was to predict water table fluctuations and to estimate the annual change in water table at an alluvial aquifer at wadi Hada Al Sham near Makkah, KSA. The methodology was achieved using numerical groundwater model (MODFLOW). The model was calibrated and then used to predict water table elevations due to pumping for a period of 5 years. The output of the model was found to be in agreement with the previous records. Moreover, the simulation results also show reasonable declination of water table elevations in the study area during the study period.
Natural ventilation is defined as the number of air exchanges per hour per unit floor area necessary
to reduce high indoor air temperature and humidity. In addition, it maintains the concentration of carbon dioxide. Natural ventilation is preferred in mechanical system as the ventilation opening is built into the greenhouse, with lower construction cost and no energy and maintenance inputs are required. A mathematical model to quantify natural ventilation rates was developed and verified in large-scale greenhouse structures. For this purpose, four Naturally Ventilated Tropical Greenhouse Structures were designed and constructed at the Malaysian Agricultural Research and Development Institute (MARDI). These were single, double, triple, and quadruple span structures with floor areas of 500 m2, 1000 m2, 1500 m2 and 2000 m2, respectively. This paper presents the validation of a mathematical model which was developed to quantify natural ventilation rates which are very crucial to reduce high in-house temperature built up in the tropics. Regression equations of natural ventilation against wind speed were found to be Φw = 0.0632V, Φw= 0.0395V, Φw= 0.0316Vand Φw=0.0276V for the single, double, triple and quadruple spans, respectively. Meanwhile, coefficients of determination showed strong relationships between ventilation rate and wind speed, with R2 = 0.9999 for all structures. Larger floor area was found to have higher in-house temperature than smaller ones. Ventilation rate inside the single-span structure was found to be higher compared to the multi-span structures, which increased linearly with the increasing wind speed at the eaves of structure.
As a crucial demand in urban areas, flood risk management has been considered by researchers and decision makers around the world. In this case, hydrological modelling that simulates rainfall-runoff process plays a significant role. This paper quantified the roles of three main parameters in river basin hydrological response, namely, rainfall event duration, rainfall event ARI (magnitude) and land-use development condition. The case study area of this research was Sungai Kayu Ara basin which is located in the western part of Kuala Lumpur, Malaysia. A total of twenty seven scenario were defined for this research, including three different rainfall event durations (60, 120 and 360 minutes), three different ARIs (20, 50 and 100 years) and in three different land-use conditions (existing, intermediate and ultimate). The results of this research indicate that rainfall event duration, rainfall event ARI (magnitude) and land-use development condition have considerable effects of the surface runoff hydrographs in terms of peak discharge and volume.
Detecting semantic events in sports video is crucial for video indexing and retrieval. Most existing works have exclusively relied on video content features, namely, directly available and extractable data from the visual and/or aural channels. Sole reliance on such data however, can be problematic due to the high-level semantic nature of video and the difficulty to properly align detected events with their exact time of occurrences. This paper proposes a framework for soccer goal event detection through collaborative analysis of multimodal features. Unlike previous approaches, the visual and aural contents are not directly scrutinized. Instead, an external textual source (i.e., minute-by-minute reports from sports websites) is used to initially localize the event search space. This step is vital as the event search space can significantly be reduced. This also makes further visual and aural analysis more efficient since excessive and unnecessary non-eventful segments are discarded, culminating in the accurate identification of the actual goal event segment. Experiments conducted on thirteen soccer matches are very promising with high accuracy rates being reported.
Controlled humidity environment is of significance in many scientific researches and experiments. In most laboratory-scale atmospheric chambers, an electrical temperature-based control system is used to adjust humidity. Since these chambers are not affordable in every laboratory, other low cost chambers using nitrogen gas or silica gel are used to adjust humidity. In this paper, a mechanism was developed to control the relative humidity in closed lab-scale chambers. Humidification is done by spraying water through a blower fan while de-humidification is by pumping air through silica gel as well as nitrogen gas injection. A Mamdani type fuzzy controller was designed to control the components and relative humidity. The results show the proposed system and controller can adjust and maintain relative humidity from 41% to 100% with maximum overshoot of 1% and the maximum range of error of steady state of 1.2 %.
The process of etching is the most crucial part of the work of manufacturing printed circuit boards (PCB). In the etching process by nitric acid, a spent etching waste solution of composition 250 g/L HNO3, 30-40 g/L Cu, 30-40 g/L Sn, 30-40 g/L Pb and 20-25 g/L Fe is produced. High metal concentrations in the spent etching waste solution make it a viable candidate for the recovery of metals. Recovery of metals from spent etching waste solution is a significant concern as the recent growth in production of printed circuit boards has generated a drastic increase of spent etching waste solution each year. This study concerns itself with the recovery of metals from spent etching waste. In this study a dilution was made in order to increase the pH of the solution as spent etching waste solution has high acidity, and the electrowinning method was performed to recover metals from the spent etching waste solution. Glassy carbon and platinum were used as cathode and anode in order to investigate the electrodeposition of metals and cyclic voltammetry investigation suggests that the deposition of metals on glassy carbon electrodes occurs at four different overpotentials mainly at -0.15 V, -0.35 V, -0.45 V and -0.75 V. Microscopy observation demonstrates that there is a deposition of metals by applying the potentials in a set of current-time transient study for a duration of 60 seconds and the metals recovered formed as aggregates.
The unified protocols are unified in application interface, models, and seamless. They generate one
standard protocol, one world called IEC 61850. IEC 61850 integrate the security, interoperability,
modelling, mapping to a substation, and reliability. Presently, the more expensive fiber based Ethernet
LAN is the most prevalent technology for medium and low voltage distribution substations. To
circumvent this problem Wireless Local Area Network (WLAN) has been investigated for its suitability
for applications that are compliant to IEC 61850: automation and metering; control and monitoring; and
over-current protection. In this paper the IEEE 802.11n WLAN is studied when used in various IEC
61850 supported applications for substation automation. It also discusses the benefits of using GOOSE
message to protect and control applications and the use of IEC 61850.
Ventilation is the process of exchanging air in a closed space to provide good indoor air quality. Computational Fluid Dynamics (CFD) has become one of the most important and reliable tools to assess natural ventilation. This paper presents the effect of wind direction on temperature and velocity inside a building with outlet windows at leeward wall and side wall. The CFD simulation was performed using Reynolds-Average Navier-Stoke (RANS) approach with k-ε model. The selection of standard k-ε model is due to suitability of this model to perform the wind speed profile and temperature profile inside the building. Validation of cross-ventilation is performed based on earlier Particular Image Velocimetry (PIV) measurements and shows very minimal discrepancy between CFD and PIV result. The result of velocity and temperature shows that the wind speed and temperature inside a building strongly depends on the incident winds angle and outlet opening of the building.
Lansium domesticum Corr. is a fruit tree of the Meliaceae family, which is commonly found in SouthEast Asia with a wide range of varieties. This study investigated three varieties of L. domesticum; Duku, Langsat and Dokong for the phytochemical screening and antimicrobial activity. Seeds from the matured fruits were extracted using hexane, methanol and water. The crude extracts were screened for antimicrobial activities toward three bacteria, namely, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus aureus. The findings showed that Langsat seed extracts contained more groups of compounds compared with the other two varieties, and its methanol extract demonstrated the highest inhibition zones against the three bacteria. The crude methanol extract of Duku seeds showed inhibition zones only towards Bacillus subtilis at a high concentration (1.0 mgL-1), whilst the seed extracts of Dokong showed no inhibition zones towards any of the tested bacteria.
Similarity measurement is a critical component in any case-based reasoning (CBR) system. CBR is
a superior technique for solving new problems based on previous experiences. Main assumption in
CBR relies on the hypothesis that states similar problems should have similar solutions. This paper
describes a comparative analysis on several commonly used similarity measures (Canberra, Clark, and Normalized Euclidean distance) in retrieving phase of the case-based reasoning approach to facilitate supplier selection. In addition, the proposed agent-based supplier selection framework was designed to use customer’s defined weights to evaluate the price, volume, quality grade, and delivery date of supply materials, and also provide them with alternative products which are closest to their first order if it was out of stock. Finally, based on the proposed framework, a numerical example of the used approach is illustrated.
Two imines of different molecular sizes namely 3-(phenylimino) indolin-2-one (PII) and 3,3- (1,4-phenylenebis (azan-1-yl-1-ylidene) diindolin-2-one (PDI) were investigated for their corrosion inhibition on mild steel in 1 M HCl solution using electrochemical impedance spectroscopy (EIS). The bigger molecule PDI containing double the amount of isatin moiety exhibited higher inhibition efficiency of 87.3% while PII that contained monoisatin moiety showed a lower inhibition efficiency of 74.8%. Both compounds had an increase in inhibition efficiencies percentage as concentrations increased. Density functional theory (DFT) was used to determine the correlation between the corrosion inhibition efficiency and electronic parameters. The DFT calculations indicated that the corrosion inhibition efficiency was mainly dependant on the frontier orbital energy gap and the chemical softness/hardness of the imines.
This study was conducted to determine the baseline water quality characteristics of a contaminated NAHRIM lake undergoing remediation by the constructed wetlands, based on the physico-chemical and biological parameters. The sampling was conducted for six months (May-October) in 2016 from 5 stations of the lake and analysed using APHA standard methods for water and wastewater analysis, while Malaysian water quality index (WQI) was used to calculate quality of the lake. The results showed that, the Conductivity, Dissolved Oxygen, NO3-N, NO2-N, PO4, Temperature, Turbidity, TDS, TSS, and Zn were under class I, while pH, B and COD were categorized under class II. NH3-N, BOD, Fe, Escherichia coli, Total coliform and Mn were categorized as class III. Moreover, Al was not given any classification under NWQS but their concentration did not exceed EPA guidelines. Furthermore, as compared to the water samples from the constructed wetlands that reported a class III WQI, the lake was observed to show an overall class II WQI. This is suggestive of the retaining and remedial role of the constructed wetlands being the first point of contact for the contaminants going to the lake. Thus the lake is suitable for recreational activities.
In this study, pressurized liquid extraction (PLE) was used with methanol as extraction solvent to extract bioactive compounds from Ananas comosus (pineapple) flesh. Response surface methodology (RSM) was used to evaluate the correlative effects of temperature (60 – 150°C) and extraction time (10 – 30 min) on the yield of selected bioactive compounds. In this model, the R2 obtained was 0.8788 for selected bioactive compounds for Ananas comosus suggesting a satisfactory agreement between the predicted and experimental values. Two-dimensional high-performance liquid chromatography (2D-HPLC) with a diode array detector (DAD) was used for the separation and detection of the bioactive compounds. Extraction temperature was found to significantly increase the yield of three selected bioactive compounds following which the optimum operating extraction conditions for PLE for Ananas comosus was determined to be 105°C and a static time of 20 min.
Skin detection has gained popularity and importance in the computer vision community. It is an essential step for important vision tasks such as the detection, tracking and recognition of face, segmentation of hand for gesture analysis, person identification, as well as video surveillance and filtering of objectionable web images. All these applications are based on the assumption that the regions of the human skin are already located. In the recent past, numerous techniques for skin colour modeling and recognition have been proposed. The aims of this paper are to compile the published pixel-based skin colour detection techniques to describe their key concepts and try to find out and summarize their advantages, disadvantages and characteristic features.
The main objectives of this study were to introduce a bubble irrigation system, compare the wetting fronts created by the bubble and free-flow systems, and test the viability of a bubble irrigation system. Two laboratory experiments were conducted using 2D flow to measure the wetting fronts. The first experiment measured the free-flow infiltration using an inverted, open plastic bottle. The second experiment tested the bubble-flow technique using an inverted, closed plastic bottle (ICPB). The results showed that the bubble-flow system created a larger width of wetting fronts at the beginning of the infiltration and then expanded less than that of the free-flow system. In contrast, the infiltration depth of the wetting fronts created by the bubble-flow system was much lower than that of the free-flow system. In conclusion, the wetting front width and depth in the bubble-flow system were slightly smaller than those in the free-flow system. In addition, the wetting fronts created by the ICPB were not moved upwards significantly, which proves the ability of specific distribution of the bubble-flow system on the wetting fronts. Therefore, the bubble irrigation system can be used as an alternative for distributing the moisture content in soil profiles.
This work was carried out with the aim to optimise the tool path by simulating the removal of material in a finite element environment which is controlled by a genetic algorithm (GA). To simulate the physical removal of material during machining, a finite element model was designed to represent a thin walled workpiece. The target was to develop models which mimic the actual cutting process using the finite element method (FEM), to validate the developed tool path strategy algorithm with the actual machining process and to programme the developed algorithm into the software. The workpiece was to be modelled using the CAD (ABAQUS CAE) software to create a basic geometry co-ordinate system which could then be used to create the finite element method and necessary requirement by ABAQUS, such as the boundary condition, the material type, and the element type.
Analyzing commodity prices contributes greatly to traders, economists and analysts in
ascertaining the most feasible investment strategies. Limited knowledge about the price
trend of the commodities indeed will affect the economy because commodities like palm
oil and gold contribute a huge source of income to Malaysia. Therefore, it is important to
know the optimal price trend of the commodities before making any investments. Hence,
this paper presents a logic mining technique to study the price trend of palm oil with other
commodities. This technique employs 2-Satisfiability based Reverse Analysis Method
(2-SATRA) consolidated with 2-Satisfiability logic in Discrete Hopfield Neural Network
(DHNN2-SAT). All attributes in the data set are represented as a neuron in DHNN which
will be programmed based on a 2-SAT logical rule. By utilizing 2-SATRA in DHNN2-SAT,
the induced logic is generated from the commodity price data set that explains the trend
of commodities price. Following that, the performance evaluation metric; error analysis
and accuracy will be calculated based on the induced logic. In this case, the experimental
result has shown that the best-induced logic identifies which trend will lead to an increase
in the palm oil price with the highest accuracy rate.
A new series of N,O-bidentate ligands, L1, L2, L3 and L4, and their Pd(II) complexes, PdL1, PdL2, PdL3
and PdL4 have been synthesised and characterised using various physico-chemical techniques, namely
elemental analyses, IR and 1
H and 13C NMR spectroscopies, and conductivity analysis. The molecular
geometries of PdL2 and PdL4 have been elucidated through single crystal X-ray crystallography revealing
2:1 molar equivalence of ligand: Pd with the Schiff bases that exhibited bidentate ligands behaviour,
in which they coordinated through the phenolic O donor atoms and imine N. Upon complexation, the
ν(C=N) around 1629-1639 cm-1 and ν(C-O) around 1251 to 1252 cm-1 shifted to lower frequencies by 4
to 23 cm-1. In this study, three parameters were chosen for the reaction conditions optimisation, which
were types of bases, loadings for the catalyst, and temperatures of the reaction. Pd(II) complexes exhibited
good catalytic activities for Heck coupling reaction with 100% conversion at 100°C within 12 hours of
reaction time. Reducing the reaction temperature to 80°C reduced the conversion to a maximum of 80%.
The purpose of this study was to develop a simple, economical but efficient procedure to collect illuminance data in quantifying interior lighting. This study was carried out in 3.8 m × 2.9 m × 3.0 m controlled experimental room. Three approaches to measure illuminance level were examined: (1) rowto-row; (2) column-to-column; and (3) zig-zag direction. A pre-determined 34 measurement points was used for all the three approaches. The duration required to complete the illuminance data measurement was recorded in minutes. There was a statistically significant difference in the total time measured to complete the illuminance data measurement in three different approaches (F(2, 4) = 23266.81, p
A non-coastal cockle farming area such as an estuaries zone might become an alternative for continuous and sustainable cockle supply in the future. The main objective of this research is to determine the growth and mortality rate of Tegillarca granosa (T. granosa) within an estuary area. Three cockle plots were allocated along the estuary area of Kongkong Laut (P1, P2, P3) based on the geographical area, from upper to lower part of estuaries. Cockle monitoring activity was conducted from August to December 2015 for both in-situ water parameters and the cockles’ growth increments. This study shows that within a brackish estuarine environment, the highest cockle growth increment was recorded within the highest water salinity trend area (26.92 ± 4.79 ppt; P2), with a shell increment of 2.70 ± 0.52 mm per month, while the lowest cockle growth increment was recorded within the lowest water salinity trend area (17.65 ± 5.73 ppt; P1) with the shell increment of 2.05 ± 0.86 mm per month. One-way ANOVA shows that there was significant difference (p