Fine resolution (hourly rainfall) of rainfall series for various hydrological systems is widely used. However, observed hourly rainfall records may lack in the quality of data and resulting difficulties to apply it. The utilization of Bartlett-Lewis rectangular pulse (BLRP) is proposed to overcome this limitation. The calibration of this model is regarded as a difficult task due to the existence of intensive estimation of parameters. Global optimization algorithms, named as artificial bee colony (ABC) and particle swarm optimization (PSO) were introduced to overcome this limitation. The issues and ability of each optimization in the calibration procedure were addressed. The results showed that the BLRP model with ABC was able to reproduce well for the rainfall characteristics at hourly and daily rainfall aggregation, similar to PSO. However, the fitted BLRP model with PSO was able to reproduce the rainfall extremes better as compared to ABC.
Notably in the construction industry, procurement is evidently important and cannot be played down because it constitutes every phase of a project delivery system. The low-bid system has remained the most popular procurement system globally. In Nigeria, it lacks transparency and accountability. Therefore, the Nigerian Procurement system has shown a need to be stabilised by shifting risk and control to the expert who has the duty to act in the client’s best interest by adopting “Best Value Performance Information Procurement System (BVPIPS)” in contractor selection. This paper aims at identifying factors that can hinder the implementation of this innovative procurement system and their relative influence. A total 314 questionnaires were distributed to 5 construction industry professionals in Nigeria they are: Architects, Quantity Surveyors, Civil Engineers, Builders and Services Engineers. The data collected were presented and analysed using: cross tabulation, exploratory factor analysis and mean score ranking using Statistical Package for Social Sciences (SPSS) version 24 and Microsoft Excel respectively. Likert scaling was used to measure the level of agreement of the respondents. The paper found out that the social factor, political factor, procurement environment factors and the cultural factor in the construction industry ranked 1, 2, 3 and 4 respectively and which factors have a very strong relative influence on hindering the implementation of BVPIPS in the Nigerian construction industry. The implication of this study is, to help construction practitioners, researchers, academics, industry players, and other stakeholders to look into the significant issues that can hinder the implementation of PIPS in Nigeria and make better the delivery of projects in the construction industry. Therefore, these factors identified should be considered and precautionary measures taken when implementing BVPIPS in the Nigerian construction industry so as to accommodate innovative approaches such as BVPIPS to improve project delivery in Nigeria.
The purpose of this research is to analyse the impact of identified variables to adapt change management
due to e-learning implementation in Malaysian private higher education institutions focusing on educators’
perspectives. The conceptual framework was modified in combination of various theories from Systemic
Change Models and E-learning Cycle Models. A self-administered questionnaire adapted from Siebel
4.0-2 Survey Questionnaires (SSQ) by Hambling, 2010 was the data collection instrument. The sample
consisted of educators from private higher education institutions with visions or missions based on
e-learning implementation in Malaysia. As per findings, through review of the visions and missions,
the selected private higher education institutions integrated teaching and learning, advancement of the
knowledge based on e-learning and leadership in service and outreach.
Concrete durability determines service life of structures. It can though, be weakened by aggressive environmental conditions. For instance, bio-corrosion process is due to the presence and activity of microorganisms which produce sulphuric acid to form sulphate deterioration of concrete materials. The problems related to durability and repair systems are due to lack of suitable concrete materials. The use bacteria for concrete repairing and plugging of pores and cracking in concrete has been recently explored. Previous studies had proved the possibility of using specific bacteria via bio concrete as a sustainable method for improving concrete properties. Thus, lack of information on the application of bio concrete exposed to extreme condition was the motivation for this research.
Carbamates are poisonous pesticides which have been used widely in agriculture production for decades. Unlike other pesticides such as organophosphate, carbamate pesticides are not persistent in the environment however, their degradation is crucial due to their toxicity to living system. The World Health Organization, categorized carbamate pesticide as toxic, hazardous and restricted for use. Example of carbamates pesticides include Carbaryl, Aldicarb, Methomyl, Carbofuran, and Propoxur. They are extensively used to control many insect and pests of crops. Presently, there is significant awareness regarding the negative effects of pesticides due to their ability to pollute soil and water bodies. Most pesticides are readily degraded or metabolized by microbes. Carbamate pesticide degradation by microorganisms relies not only on the availability of microbes with suitable biodegradative enzymes, but also on the various ecological factors. This reviewarticle outlines the present development in biodegradation of carbamate pesticides, their toxicity and enzymatic degradation as well as their degradative pathways.
This paper highlights a potentially life threatening and unsuspected case of multiple small pseudoaneurysms from the thyrocervical and costocervical branch of the left subclavian artery that was spontaneously ruptured. The cause was not suspected prior to thoracic CT angiography (CTA) because the initial pre-emptive diagnosis was only trivial spontaneous hydropneumothorax which became serious after a chest tube was inserted.
Diabetes is one of the major life-threatening health problems worldwide today. It is one of the most fastgrowing diseases that cause many health complications and a leading cause of decreasing life expectancy and high mortality rate. Many studies have suggested several different types of intervention to treat Type 1 diabetes such as insulin therapy, islet transplantation, islet xenotransplantation and stem cell therapy. However, issues regarding the efficacy, cost and safety of these treatments are not always well addressed. For decades, diabetes treatments with few side effects and long-lasting insulin independence has remained one of the most challenging tasks facing scientists. Among the treatments mentioned above, application of human islet transplantation in patients with type 1 diabetes has progressed rapidly with significant achievement. Again, the lack of appropriate donors for islet transplantation and its high cost have led researchers to look for other alternatives. In this review, we discuss very pertinent issues that are related to diabetes treatments, their availability, advantages, disadvantages and also cost,
The feasibility of an anaerobic digestion of cattle manure for biogas production is studied in this paper.
A batch thermophilic oscillatory flow anaerobic bioreactor (OFBR) operated in thermophilic (55o
C)
condition was used. Within the experimental conditions set in this study, the effect of mixing intensity on
volatile solids removal was found out to be significant. Results demonstrated that increasing the level of
mixing decreased the digester performance. Low intensity mixing at oscillatory Reynolds number (Reo)
of 100 achieved an increase of 37% in biogas yields compared to high mixing intensity, Reo of 500. It
was observed that the mixing intensity effect interacts with the methane composition in the biogas. The
benefit of decreasing mixing intensity emerges to significantly increase the methane composition in the
biogas. These experiments established that high intensity mixing was not essential for good performance
of oscillatory flow anaerobic bioreactor. In addition, the effect of mixing intensity might be reduced
through the use of a slightly lower total solid concentration, hence, lowering the operational cost of the
process. Although the study was lab scale a pilot-scale system where mixing retention times are longer
would be useful.
The effect of osmotic stress was carried out to determine the resistance to salt toxicity using 4 Continuous
Stirred Tank Reactor (CSTR). A CSTR digestion study revealed that digesters seeded with an inoculum
from a conventional mesophilic digester treating municipal wastewater and fed on domestic wastewater
(DW) plus salts were able to acclimate successfully to a final salt concentration of 10 g l-1. The digesters
showed some disturbances during the acclimatisation period as indicated by reductions in specific methane
production (SMP), specific biogas production (SBP), pH and increases in Intermediate Alkalinity /Partial
Alkalinity (1A/PA) ratio and Volatile Fatty Acid (VFA) concentration. This study revealed the order
of disturbance was Sodium Chloride (NaCl) > Potassium Chloride (KCl) > KCl + NaCl. The average
values for SMP after stabilisation were below those in the controlled digester, at 0.335 (controlled),
0.323 (NaCl), 0.316 (KCl + NaCl) and 0.308 l CH4 g-1 COD added (KCl).
Geographic Information System (GIS) and remote sensing are geospatial technologies that have been used for many years in environmental studies, including gathering and analysing of information on the physical parameters of wildlife habitats and modelling of habitat assessments. The home range estimation provided in a GIS environment offers a viable method of quantifying habitat use and facilitating a better understanding of species and habitat relationships. This study used remote sensing, GIS and Analytic Hierarchy Process (AHP) application tools as methods to assess the habitat parameters preference of Asian elephant. Satellite images and topographical maps were used for the environmental and topographical habitat parameter generation encompassing land use-land cover (LULC), Normalized Digital Vegetation Index (NDVI), water sources, Digital Elevation Model (DEM), slope and aspect. The kernel home range was determined using elephant distribution data from satellite tracking, which were then analysed using habitat parameters to investigate any possible relationship. Subsequently, the frequency of the utilization distribution of elephants was further analysed using spatial and geostatistical analyses. This was followed by the use of AHP for identifying habitat preference, selection of significant habitat parameters and classification of criterion. The habitats occupied by the elephants showed that the conservation of these animals would require good management practices within and outside of protected areas so as to ensure the level of suitability of the habitat, particularly in translocation areas.
This paper discusses the harmonic analysis of the AC-to-DC uncontrolled converters commonly used in electric vehicles charging station. The aim of this paper is to model and simulate different rectifier models in addition to explaining the differences in input current harmonics, the total Harmonic Distortion (THD) as well as the power factor (pf). The converter configurations include single-phase bridge, 6-pulse and 12-pulse rectifier circuits. The single phase is normally used for electric scooter charging, while three-phase converters can be used for both electric bus and car charging. The circuit configurations of the rectifiers were modelled and simulated using Matlab R2014a to achieve the objective of the study. The results revealed that the THD levels were extremely high which is unacceptable if the system is connected to the utility grid.
Agarwood or gaharu, due to its unique scent and quality is considered one of the most expensive wood in the world. This paper uses solvent trap, Gas Chromatography-Flame Ionization Detector (GC-FID) and Gas Chromatography-Mass Spectrometry (GC-MS) to establish agarwood quality, and is part of ongoing research. The result showed that monoterpenes hydrocarbon, sesquiterpenes hydrocarbon and oxygenated sesquiterpene contribute to agarwood smoke. Among many compounds extracted, 2-hydrdoxy-benzaldehyde, β-selinene and guaia-1(10),11-dien-15,2-olide were found dominant in monoterpenes hydrocarbon, sesquiterpenes hydrocarbon and oxygenated sesquiterpenes respectively. This finding pointed to the utility of solvent trap in extracting chemical compounds of agarwood smoke. This study is also useful for further research on establishing the grade of agarwood.
Single Stock Futures (SSFs) was introduced in Bursa Malaysia on 28th April 2006. There have been many studies on derivative instruments in Malaysia; however, none is on SSFs. Various statistical methods have been used to analyse the SSFs and its spot returns, namely Descriptive Statistics, Unit Root test, VAR, Johansen and Juselius Co-integration test, Granger Causality test, Variance Decomposition test, VECM, and GARCH model. This study analyses the SSFs and spot returns of eight companies listed in Bursa Malaysia. It found that Berjaya Sports Toto Bhd and Genting Bhd have no long-run and short-run causality (Genting Bhd has bi-directional causality) while AirAsia Bhd and AMMB Holdings Bhd’s spot returns’ volatility decreased after the introduction of SSFs; it increased in the other seven companies. In addition, only AMMB Holdings Bhd futures return did not affect its spot return. Bursa Malaysia Bhd and RHB Capital Bhd spot returns lead their futures returns
A numerical simulation and analysis was performed to investigate the effect of absorber and buffer layer band gap grading and on a Copper-Indium-Gallium-Diselenide (CIGS) solar cell. The software used is the Solar Cell Capacitance Simulator (SCAPS). The absorber and buffer layer energy band structures’ effect on the cell’s output parameters such as open circuit voltage, short circuit current density, fill factor and efficiency were extensively simulated. Two structures of the energy band gap were simulated and studied for each of the absorber and buffer layer. The simulation was done on the uniform structure in which the energy band gap is constant throughout the layer. It was then continued on the cell with graded band structure, where the energy band gap of the material is varied throughout the layer. It was found that the cell with graded band structure in absorber and buffer layer had demonstrated higher efficiency and better performance in comparison with the cell with uniform band gap structure.
Lightning is a natural phenomenon that generates a high electric field during thunderstorm. It has been
reported that lightning strikes amid storms can occur around 100 times per second. The atmospheric
electric field is an imperative parameter during a thunderstorm. Therefore, monitoring the electric field
and its parameters is the best way for local lightning forecast. The electric field monitoring data can
validate the accuracy of weather prediction in a local area from meteorology department or by using
equipment specially designed to measure this electric field that exists when the phenomenon of lightning occurs. In this paper, the relationship between lightning, air humidity and temperature is discussed to understand the post lightning effect on these electric parameters. Additionally, the characteristics of the parameters are observed and analysed.
Pineapple (Ananas Comosus), which has been identified as high-value non-seasonal tropic fruit, is one
of the top five fruits in Malaysia that shows a promising demand in the local and export markets. The
current study was conducted to analyse the efficiency energy inputs used in every activity involved in the
process of pineapple production. The study also aimed to contribute in initiating a database for energy
used in producing pineapples in Malaysia, which would hopefully become a guideline for applications
in related policies in pineapple plantations. Data were collected based on direct field observations at a
pineapple plantation under the management of Koperasi Serbaguna Anak-Anak Selangor Bhd. (KOSAS
Bhd.) at Kg. Kundang in Selangor, Malaysia. Oral interviews were also carried out to gather any relevant
information. The highest energy input used in pineapple production is fertiliser, contributing to 45.65%
from the total energy equivalents used in the production. Fuel is the second highest energy source with
a segment of 20.21% of the total energy, followed by planting material, agrochemicals, human labour
and machine at 17.33%, 12.76%, 3.34 % and 0.69%, respectively. The ratio of energy output/inputs in
pineapple production in the study area was 3.56. Conclusively, it means the energy input is effectively
used in the pineapple production in the study area since the energy output/inputs ratio is greater than 1.
Involvement of machinery in the pineapple cultivation practices in Malaysia is recommended since it
reduces human drudgery and optimises farm’s capability to do work more efficiently and also to offset
the labour shortage problem.
In recent years, injection moulding process is one of the most advanced and efficient manufacturing processes for mass production of plastic bottles. However, a good quality of parison is difficult to achieve due to uncontrollable humidity, pressure inlet and water inlet velocity. This paper investigates the effect of using multiple mould cavities to improve the process fill time and injection pressure in the production of PET plastic bottles using MoldFlow software. The modelling of parison was developed using CATIA with the consideration of every part of the parison. MoldFlow software was used to analyse the flow of 20 g parison with different cavity numbers (1, 8, 16, 24 cavity), as well as its corresponding runner size towards its fill time and injection pressure. Other important parameters that affect the production of parison, such as melting temperature, mould temperature, atmospheric temperature and cooling time, were remained constant. The fill time required to produce 24 moulds was improved by 60% compared to using 8 mould cavity only, and this enable the production of more plastic bottles in a day. Therefore, fill time and injection pressure are two important parameters to be considered in the injection moulding process, especially to reduce parison defect and increase its production rate.
The grounding system of a lightning protection scheme is designed basically to avoid arcing and
dangerous step potentials. The grounding impedance of the system varies depending on soil structure and frequency. This paper describes the effect of harmonic impedance (also called frequency dependence of soil) on potential distribution under lightning strike to a metal tower with single grounding path, for different soil types. The results show that the peak value of ground potential rise (GPR) and step voltage (SP) may reach extremely hazardous values even at distances in the order of 90 m from the tower footing, especially when soil resistivity is high. Hence, we emphasise that, in contrast to power grounding, when designing of grounding systems that are meant to handle transient or high frequency currents as well, the frequency dependent soil parameters should be considered to avoid hazardous situations, especially at locations with a high probability of lightning strikes such as metal towers.
In order to ensure the optimum quality of palm oil, oil palm fruit needs to be harvested at the optimum maturity to avoid free fatty acid (FFA) accumulation. The high content of FFA not only reduces the quality of palm oil but also increases the refining cost. Optimum maturity based on plantation standard operating procedure (SOP) is determined by identifying the tree with loose fruit on the ground. The matured bunch is further identified based on the colour of the bunch. This paper presents a research work on formulation and validation of mathematical equations to estimate the maturity stages (age in weeks) of fresh fruit bunch (FFB) based on FFB position in oil palm phyllotaxis (spiral leaves arrangement) as an additional feature to confirm the maturity level of oil palm FFB. Regression analysis showed that the proposed method was able to estimate the maturity stages of oil palm FFB with the coefficient of determination R2 = 0.9 and a root mean square error (RMSE) of 1.58 weeks. The FFB yield estimation model and harvesting can be created based on the extracted data using the formula which will help in the planning of harvesting operation. Plantation manager can use this information to generate yield variability map and estimate the appropriate number of workers and machine. Planned harvesting operation can save a significant amount of time in site harvesting operation.
Synthesis of carboxymethylcellulose (CMC) from natural cellulose is an important industrial process. The effect of process parameters on the synthesis process is important information for the efficiency improvement of production process. Most of the previous studies on the effect of process parameters
on the synthesis of CMC are based on the One-Factor-At-Time (OFAT); therefore, in this work, the response surface methodology (RSM) was used. Here, the cellulose was converted to CMC through
carboxymethylation process using a technique of William etherification in heterogeneous system. The process parameters studied include the solvent ratio, reaction temperature and reactant ratio (molar ratio of NaOH to SMCA). Meanwhile, the analysis and optimization of the responses of the process, degree of substitution (DS) and yield were also performed using the response surface methodology. The validity of the synthesis process was identified by the determination of CMC spectrum using the fast Fourier infrared spectrometer (FTIR). The analysis of the results shows that carboxymethylation is strongly affected by combination of process parameters studied. The results obtained also show that the optimum responses, degree of substitution (DS) is 0.87 and yield is 1.80, whereas the optimum process parameters, solvent ratio is 0.70v/v, reaction temperature at 56.03oC, and molar ratio of NaOH to SMCA at 1.00mol/mol. These findings conclude that the DS and yield of carboxymethylation of cellulose are strongly affected by the combination of the process parameters.