Special Issue 4(2) 2021
Chief Guest EditorAssoc. Prof. Dr. Fakroul Ridzuan Hashim National Defence University of Malaysia
Guest EditorsDr. Mohd Faizal Abdullah, Dr. Maidiana Othman & Mr. Mohd Salman Mohd Sabri National Defence University of Malaysia
The theme for this issue of the Engineering Journal is on the research and application among academicians, researchers and industries in science and technology (especially in defence & technology, but not limited to). Full length papers, reviews and short communications are welcomed, on subjects such as experimentation (both techniques and data), new theoretical models, commentaries work and letters to the editor.
Table of Contents
M. M. Ariffin, M. T. Ishak*, M. H. A. Hamid, F. R. Hashim, M. F. Md Din & R. Abd Rahman
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-01
This paper presents a sealed ageing study of palm oil, corn oil, and rice bran oil with and without the presence of insulation paper. The oils were aged at four different durations which are at 2 days, 30 days, 90 days, and 180 days at a constant temperature of 90°C. The properties of vegetable oils as well as insulation paper under ageing were then analysed through AC breakdown voltage, dielectric losses, relative permittivity, resistivity, moisture, and acidity of the oils. It is found that the AC breakdown voltage of oils with the presence of insulation paper is lower than the oils without the insulation paper. The AC breakdown of oils with and without insulation paper increase with the ageing time which reflect the amount of moisture in oil. For dielectric loss, the value is increased with time and dielectric loss with paper shows lower value than without paper. RBO shows higher dielectric losses for both conditions. In term relative permittivity, it can be concluded that the relative permittivity increases when the time ageing increase. It is seen that relative permittivity of palm oil is the highest change in duration of time ageing from 1.8 to 2.0 for both conditions. Throughout the ageing time, the acidities of all the oil samples remain at low level for ageing without paper. However, with the presence of paper, the number of acidities for all oil samples increased with the time. With the presence of Kraft paper, the viscosity will decrease over time duration. But, without the presence of Kraft paper, the viscosities were almost stable for all samples.
Keywords : Ageing; temperature; kraft paper; vegetable oils
A. H. Isahak, M. F. Abdullah*, M. K. Faidzi, W. Y. W. Yusof, S. Abdullah, A. Ali & M. M. Mubasyir
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-02
The armoured vehicle uses a special solid steel that has a heavy vehicle ratio which causes the performance to decrease after being triggered by high velocity impact bullet on rescue missions thus experiencing the phenomenon of fatigue and unstable crack growth flow. In this study, an investigation on crack growth behaviour was carried out for sandwich metal panel and solid High Strength Steel (HSS) which has high ability in terms of residual life. Meanwhile, sandwiched metal panel contains HSS as face sheets and lightweight material as a solid core. The main objective of this study was to determine the crack growth behaviour on two types of structural material by applied frequency (f=10 Hz), stress ratio (R=0.1), and thickness (10 mm) as a constant parameter. The crack growth experiment used compact tension (CT) specimen as followed the ASTM E647 standard. The benchmark for establishing the crack growth behaviour is the (a-N) graph and the Paris law regime, da/dN against stress intensity in order to determine Paris constant (C and m). Based on the results, the sandwich metal panel is more applicable with the number cycle of N = 23300 with an increase in about 27% compared to solid HSS. It can be concluded that the sandwich metal is most practicable and affordable for using higher level of threat for hard armour vehicle panel.
Keywords: Armour vehicle; crack growth; high strength steel; sandwich metal panel; Paris law regime
Vikneswaran Munikanan*, Ng Choy Peng, Muhamad Azani Yahya & Mohammed Alias Yusof
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-03
Road line marking are used as a mean of controlling traffic and road user safety. It is very significant on any roads and intersections as they promote road safety. They highlight a harmonious flow of traffic along guided paths of travel. The objectives of this study are to investigate the properties of road line materials and examine the illuminance properties of glow in the dark powder applied in road marking materials. The use of photoluminescent glow-in-the-dark material was tested in the lab for its suitability (luminosity and the glow duration). The methods involved are selection of suitable type of glow in the dark materials, selection of optimum mixing ratio of the glow in the dark powder with thermoplastic powder, and finally analyzed for the properties of the type of the material chosen. The fine granular strontium aluminate compound, SrAl2O4 was selected as the most suitable type of glow in the dark material. Based on the laboratory analysis, the optimum ratio of the glow in the dark material to be used with thermoplastic powder is 55% of total mix volume. The average visible light emission period is in acceptable range of 20 m. This is a suitable distance to implement the road line because of the high visibility on the road during dark or night.
Keywords: Road line; photoluminescent; luminosity; glow in the dark; thermoplastic
Dildar Hussein, Khairol Amali Ahmad*, Ahmad Zulhelmi Mat Nizan, Nazrul Fariq Makmor & Fakroul Ridzuan Hashim
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-04
Concerns over security for energy sources have led many countries to concentrate on obtaining renewable energy sources. In fact, Malaysia has also studied various alternative energy sources including wind energy. However, the terrain of Malaysia does not allow strong winds to move the wind turbines. Therefore, initial efforts to harness energy from the wind were not very successful. Therefore, this study has improved previous studies by highlighting the concept of vertical axis wind turbine using Magnus effect concept.
Keywords: Energy security, renewable energy, Magnus vertical wind turbine, slow wind energy generation
M. M. Mubasyir, M. F. Abdullah*, K. Z. Ku Ahmad, R. N. I. R. Othman & A. H. Isahak
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-05
This paper focuses on improving energy absorption through a series of heat treatment and quenching in medium, presence of nanoparticle. The characterisation of the experiment was to determine the suitable combination of composition factors: temperature, soaking time, and the medium that consist of nanoparticle on magnesium alloy surface structure to improve the energy absorption using quenching in nanofluids. The diameter and thickness of the specimen are 6 mm and 10 mm, respectively. All specimens undergo heat treatment based on the temperature of the furnace and the soaking time of the specimen in the furnace, which will be submerged into three medium distilled water, and the addition of a 0.1% wt carbon-nanotube (CNT) and 0.1% wt nano-silica. The addition of CNT and nano-silica shows an increment of 106.68%% and 59.30% for energy absorption, respectively, when compared to the controlled sample. Later microscopy has performed on the specimen to correlate the addition of nanoparticles in the heat treatment and improved energy absorption by EDS analysis on the material composition on the specimen’s surface. Therefore, this paper reveals factors of heat treatment and the presence of CNT and Nano silica effects on enhancing magnesium alloy energy absorption: UTS and yield strength using quenching method.
Keywords: AZ31B; CNT; nano silica; quenching
Muhamad Azani Yahya*, Mohammed Alias Yusof, Vikneswaran Munikanan, Siti Khadijah Che Osmi, Nordila Ahmad & Jestin Jelani
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-06
The usage of bollard is very important in protecting buildings. It can prevent vehicles from passing through the building. But the public now is less sensitive about the use of bollards. They assume the use of bollard is wasteful and for aesthetic only. Therefore, most buildings did not install bollards to protect the building. Besides that, there are also mounted bollards installed that are inappropriate to that place. For example, some bollards installed around buildings are not concrete type that can withstand strong impacts. Furthermore, some important and historic buildings need to install an explosive-proof type of bollard as building protection. The methods used for this research were non-destructive test and destructive test. Non-destructive test is slump test and destructive tests are compression test, tensile test, flexural test, and air blast test. Seven mix were used and tested in this research. From the compression test result, it shows that concrete mixed with 0.5% of macro synthetic is much stronger than control sample and other mixtures. From the tensile test, it shows that the control sample of the concrete achieved tensile strength of 3.48 N/mm2 while the mixed concrete with 0.5 % mix of macro synthetic fiber gave higher tensile strength. The flexural test shows that the concrete mixed with percentage ratio of 0.5%, 1.0%, and 1.5% of macro synthetic fiber gave higher strength than the control sample which is only 2.77 N/mm2. Based on experiments that have been carried out, it can fulfil objective one, which is to evaluate the type of blast safety for building envelope with the concrete bollard grade 30. Quality of concrete in terms of strength, tensile, and flexure of the proposed material with 0.5% of macro synthetic fiber can produce the same quality and meets the quality grade C30 concrete.
Keywords: Bollard; high-tensile concrete; synthetic fiber
Fina Supeginaa, Yuliza, Fadli Sirait, Muhamad Faiz Md Din, Nazrul Fariq Makmor & Mohd Taufik Jusoh*
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-07
Hydroponics is one of the cultivation methods that uses water as a plant growth medium. In this technique, a mineral solution is added to the water solvent, which enables the process of nutrient uptake by the plant. Several important parameters need to be observed to use hydroponic cultivation methods such as temperature, humidity, water, and nutrient requirements. Sunlight is also needed for the process of photosynthesis to take place. This research uses hydroponic techniques in a hydroponic growth space, with LED growth lights as an alternative to sunlight because the space is covered without sunlight. Monitoring of the output in the box was detected using a temperature sensor, a humidity sensor, an ultrasound sensor to detect the height of the plant, and a water level sensor with the height of the water measured as the plant medium. The sensor measurement results in the hydroponic growth chamber are described as follows: the fan cooler operates when the temperature is > 30oC, and the humidity > 60%. The water pump works when the water level is less than 50% of the set point. Control on the lights was carried out with the LDR sensors each reaching a setting point of >500 in bright conditions, and <500 in dark conditions. The average update / data time received in the web is 2.4 seconds.
Keywords: Control system; hydroponic; water level; monitoring
Nordila Ahmad*, Zuliziana Suif, Maidiana Othman, Wan Mohamed Syafuan Wan Mohamed Sabri, Muhamad Azani Yahya & Ahmad Naqiuddin Azha
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-08
Vegetation affects sediment transport by obstructing the flow and changing the turbulence characteristics. Common sediment transport equations are not applicable to situations with submerged vegetation. A laboratory experiment was carried out in which flow, vegetation, and sediment transport were measured in an open channel model with a 240 cm long section of 50 cm high x 50cm width with submerged vege-tation in a sand bed. Measured data from various vegetation density and height were analyzed to obtain estimates of the trapping efficiency. Results show an increment of the trapping efficiency with 86.7% and 94.2% reduction in sediment concentration compared to a case without vegetation.
Keywords : Vegetation; sediment transport; sediment trapping; efficiency; suspended sediment
Raja N Othman* & Muhammad S. Zainordin
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-09
Thermally conductive polymer composites offer new potentials for replacing metal parts in numerous applications, including power electronics, electric motors and generators, heat exchangers, and so on. Current interest to enhance the thermal conductivity of polymers is focused on the selective addition of nanofillers with high thermal conductivity. Therefore, graphene is the best choice material for thermally conductive composite. This study focuses on conducting the experiment to measure the thermal conductivity of graphene based epoxy nanocomposites with various variables and preparation conditions. Along this project, a series of experiment is done by manipulating the graphene loading ratio, the stirring rate, and the stirring time. 34 samples were prepared, tested, and analysed in order to determine the composite samples with the optimum variables. At the end of the experiment, the highest thermal conductivity of graphene based epoxy nanocomposites is identified at 0.204 W/mK. The optimum variables and conditions that came out with the best result are 0.3 wt% of graphene loading and 500 rpm of stirring rate at 30 minutes of stirring time. The enhancement of the thermal conductivity is 19.53% higher than that of the neat epoxy alone which is 0.17067 W/mK. This project is expected to serve as a good reference for future studies.
Keywords: Graphene; thermal conductivity; epoxy nanocomposites; rules of mixture; series model
Dildar Hussain, Mohammad Omar, Khairol Amali Ahmad, Ja’afar Adnan & Khaleel Ahmad*
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-10
When database is stored in one computer or server, certain issues related to disaster (in terms of natural or un-natural) problem may arise with reference to geographical connection and geographical distribution of servers. Here, replication feature plays an important role. There were many techniques and methodologies for geographically distributed servers, but the problem was of one master. When an authorized user updates his database on a client database server then this client database server updates his master database server and at last, the master database server updates all its client’s database servers. The described process is called database replication. In this process, there are several main parameters that are important, i.e., bandwidth, memory, and processor time. In this paper, the analysis is focused on comparing which database (NoSQL family-RethinkDB and MySQL) utilize how much memory, processor, and time during replication of database from client to master.
Keywords: MySQL; NoSQL; replication; Master and Slave Database; USN; DRBD; RSYNC
Mohd Asri Md Nor*, Nabihah Mohd Nazir, Shahrul Sahusi & Zuliziana Suif
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-11
This paper presents the results of performance monitoring of wastewater treatment systems installed at Universiti Pertahanan Nasional Malaysia (UPNM). UPNM is a military-based university located in Sungai Besi Camp, Kuala Lumpur, Malaysia. As the university expands, new buildings were constructed and new prefabricated sewage treatment plants (STPs) were installed. Effluent of these STPs were monitored and compared with required standards. Effluent samples were collected from three STPs for three months and tested for parameters of pH, temperature, biochemical oxygen demand (BOD), chemical oxygen demand (COD), ammoniacal nitrogen, nitrate, and phosphorus. The results were then compared with the standard B of the Environmental Quality (Sewage) Regulations 2009. Diurnal fluctuation of the effluent quality was also studied. From the data observed, it shows that the performance of the wastewater treatment plant is good. The effluent quality also achieved the allowable standards set by the authority. Maximum diurnal fluctuation was observed for COD which fluctuated between 18 and 52 mg/L which is still lower than standard B for COD effluent limit of 200 mg/L.
Keywords: STP; wastewater; wastewater treatment plant; sewage; UPNM
Raja N Othman* & Abdul. H. Zainudin
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-12
In this research, tensile test was conducted to reveal the notable enhancement of Young Modulus and tensile stress composites. Epoxy resin is a cross-linked polymer, thus it has major influence on the properties of polymers generally in hardness, strength, stiffness, brittleness, and better dimensional stability. Epoxy resin plays many roles in industry especially in adhesion process in automotive and aerospace composites. Discovered in 2004, graphene has revealed that it has tremendous mechanical properties and thermal properties. On top of that, addition of graphene to epoxy can lead to innovate in various adhesion industry and structural materials. In this project, an experiment was conducted in various phases which varying with graphene loading ratio, stirring speed, and stirring time. Outcome from this experiment showed that 1.0% of graphene loading with 500 rpm stirring speed and 30 minutes stirring time shows the optimum condition to enhance the measured properties. The enhancement showed are 53.03 % of Young Modulus and 51.19 % for tensile test result compared to the preliminary result. This study clearly stated the enhancement of mechanical properties of epoxy composites by merely adding 1 wt.% graphene.
Keywords: Graphene; Young Modulus; Tensile Stress; Epoxy Nanocomposites
Muhazam Mustapha*, Jeffery Lee, Anis Shahida Niza Mokhtar, Kamarul ‘Asyikin Mustafa & Bakhtiar Affendi Rosdi
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-13
The current CMOS’s industry standard XOR and XNOR gate consist of 12 and 10 transistors, respectively. This transistor count could be lowered down to produce low power circuits as XOR/XNOR are extensively used in many functional modules. As a solution, a method for realizing low transistor count XOR/XNOR gates using a special property of symmetric Boolean function is proposed. This property suggests that the circuits for such functions can be realized with fewer transistors using a special lattice structure circuit. Modifications are made to the original lattice structure to match with the current CMOS technology requirements. The final circuits require eight transistors each for XOR/XNOR with mixtures of NMOS and PMOS at push-up and pull-down networks. Simulations show that the intended logic functions of XOR/XNOR are achieved. The reading of actual voltage swing, however, shows that the output is either 0.3 V over ground or below VDD when there is a mixture of NMOS and PMOS as pull-down or push-up networks, respectively. More voltage loss of 0.4 V is observed if only NMOS is at push-up or only PMOS is at pull-down networks. As a preliminary work, this achievement of the functional logic level warrants more future work to improve the loss in output voltage swing.
Keywords: XOR; XNOR; symmetric Boolean function; pass-transistor logic; CMOS; lattice structure
Sivadass Thiruchelvam*, Nurainaa Kabilmiharbi, Fevilia Nurnadia Adria Syaifoel, Zubaidi Faiesal Mohamad Rafaai, Azrul Ghazali, Kamal Nasharuddin Mustapha & Rahsidi Sabri Muda
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-14
Work at fossil-fuelled power plant is physically strenuous and could expose workers to Work-related Musculoskeletal Disorder (WMSD) such as Carpal Tunnel Syndrome (CTS), low-back pain (LBP), or shoulder tendonitis. WMSDs are considered as a leading factor in disabilities and absenteeism, reduced production, and increased costs. WMSDs in the workplace have been studied extensively and it is a common notion that the work itself is a major cause of MSDs. Work environment contributed to these types of disorders and are made worse by the working conditions or workplace risk factors. All those mentioned common occupational injuries are related with the ergonomic field of study. By implementing appropriate ergonomic interventions, the above-mentioned work-related injuries and resulting disability is potentially preventable. The major workforce in these plants are either associated with handling of machineries or serving as control room operators. Hence, this category of manpower is subjected to physical stress and workplace injuries if there is no form of ergonomic interventions. Previous studies have shown that common tasks performed by workers in the electric power industry often involve the use of a manual tool and revealed that less than 1% of the general population has sufficient strength to manually perform the task resulting in decreased productivity and worker injury. Departing from the aforementioned need, this study embarks to assess exposure to risk factors for WMSDs and to provide a basis for ergonomic intervention at the workplace. Therefore, by focusing on health and safety matter of workers at our power plants, we are actually applying a form of business risk management (BRM) to consider possible impacts of related foreseeable significant risks on any electricity utilities performance. It is envisaged that this study could identify the ergonomics interventions which will reduce staff medical bills, compensation, and lost time injury from MSDs.
Keywords: Ergonomics; occupational safety and health; power plant
Haziq Idraki Shahidin, Mohd Rosdzimin Abdul Rahman, Azam Che Idris & Mohd Rashdan Saad*
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-15
Traditionally, wind tunnel models are made of metal and the processes are very expensive. Since then, many researchers have been looking for new alternatives, hence 3D printing technology is the solution. Under right test conditions, 3D printed parts could be tested in a wind tunnel to get the aerodynamic performances. By using 3D printing technology, the cost and time can be significantly reduced to produce the wind tunnel models. This investigation was done to compare the aerodynamic performances which are drag and lift forces of the existing wind tunnel metal models with 3D printed wind tunnel models. Polylactic acid (PLA) was used as the printing materials by using two 3D printers which are Poseidon X and CR-10 S5. The wind tunnel testing covered the wind speed in the range of 0.57 m/s to 10.35 m/s at angle of-attack of 0°. Results from experiments show that the drag and lift forces of the 3D printed models show very close similarities with the metal models. It can be concluded that the wind tunnel models produced by using 3D printing technology can be used in wind tunnels for early testing.
Keywords: 3D-printing; wind tunnel; aerodynamics
A. Miskon*, M. S. Salleh, S. N. M. Tawil, Mohd Salman Mohd Sabri & N. R. S. Rokmanuddin
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-16
Transcutaneous Electrical Nerve Stimulator (TENS) is a device that can stimulate the nerves by using electric current. The main role of TENS is as a pain relief to users by replacing the usage of analgesic or drug. 2-Channel Defence Transcutaneous Electrical Stem Stimulator (2-Channel DTES) device and 5-Channel Defence Transcutaneous Electrical Stem Stimulator (5-Channel DTES) has been developed to improve the previous TENS devices but there were some shortcomings of the devices such as incoming noise in circuit as well as different measurement results if compared to simulation and experimental test. These problems may be solved by designing an alternative circuit of TENS to overcome the noise issue appearing during testing in which this study has tested and analyzed the basic circuit of TENS unit. Even though an issue of incoming small amount of generated electric current, apparently it would not affect the patient by using TENS. The capability of TENS as pain relief has been demonstrated to be comfortable, user friendly, and highly efficient to the user. From the experimental, it has been observed that the percentage measured for period of time, T from 900 Hz to 1820 Hz output measurement using implementation without electrode pads and with electrode pads of Transcutaneous Electrical Nerve Stimulator for biomedical application is around ± 5%.
Keywords: Bio-composite; SolidWork; Wood composite; Impact test
Sivadass Thiruchelvam*, Kamal Nasharuddin Mustapha, Lee Choon Yong & Rahsidi Sabri Muda
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-17
This paper presents the experimental work on typical Malaysian silty residual soils in order to evaluate fundamental soil properties in particular its stiffness under low frequency cyclic loading. There has been very little information on local silty residual soils which is very important for local geotechnical design purposes. Lack of such information contributes to the dependency of foreign soil data which might not be representative of local silty residual soils. This study departs from the basis of there have been verified evidences that we are not spared from seismic activity in Malaysia. Hence, it would be misleading if we were to exclude soil properties under cyclic loading for design purposes in Malaysia. This research revolves around the development of simplified device to evaluate the stress-strain behaviour of soils under simple shear strain conditions. The cyclic loading test results on Malaysian sedimentary residual soil sample exhibit increase of drained shear stiffness, GSTIF and gained strength after 30 cycles indicating cyclic hardening behaviour. It is evident that magnitudes of cyclic load and cyclic displacement influences the rate of soil volume change. Nevertheless, the densification of soil samples due to increment of cycles caused reduction in volume change. It is foreseen that the obtained parameters could assist in the practical geotechnical engineering problems related to cyclic conditions.
Keywords: Cyclic; simple shear; loading; shear stiffness
Mohd Fazli Mohd Yusoff*, Ahmad Mujahid Ahmad Zaidi, Saiddi Ali Firdaus Ishak, Mat Kamil Awang & Muhamad Faiz Md Din
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-18
This paper presents the review of electromagnetic damper as a vibration/isolation material. A bunch of articles about vibration and suspension system was reviewed and the key factors that contribute to electromagnetic damper was identified. Electromagnetic damper has been given special attention from many researchers and thus being among the important research area in vibration system. Vibration concept of electromagnetic damper has been elucidated by referring to several paper that demonstrate the usage of electromagnetic damper. Finite element magnetic method (FEMM) software has been used in order to identify the best configuration of geometry in the system. A simulation in Matlab was done by considering a quarter car model with a theoretical value from the Faraday’s Law equation involved in electromagnetic damper. The slotted and cylindrical geometry configurations have been simulated using FEMM and the result clearly shows that the slotted configuration has a better effect on the electromagnetic damper system.
Keywords: Electromagnetic damper; eddy current; vibration; suspension system
Mohd Taufiq Ishak, Mohd Taufik Jusoh, Jaafar Adnan & Rahisham Abd. Rahman
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-19
The performance of liquid insulation in power transformer is vulnerable to particles, especially the metallic particles. This paper presents the experimental study on the effect of metallic particles on the palm oil (PO) as dielectric insulating fluid under lightning impulse breakdown voltage. The type of PO used in this study is refined, bleached and deodorized Palm Oil (RBDPO) Olein. Two different types of metallic particles (copper and iron) with different concentrations (clean, low, medium, and high) were studied. The lightning impulse test has been carried out according to IEC 60897 standard and under the influence of a uniform electric field. For the comparative purpose, similar test has been carried out with mineral oil (MO). The presence of metallic particles reduces the average lightning impulse breakdown voltage of MO and PO but shows less significant effect to MO. This is because the streamers in the PO propagate faster and further than in the MO at the same voltage level. Hence, causing the breakdown voltage of PO lower than MO. Under negative lightning impulse, the breakdown voltage of MO is slightly higher than RBDPO. From the study, the increment of the number of particle level contamination will reduce the lightning impulse breakdown voltages of the PO.
Keywords: Mineral oil; palm oil; metallic particles; lightning impulse breakdown voltage; uniform field
Azrul Ghazali*, Sivadass Thiruchelvam, Kamal Nasharuddin Mustapha, Rahsidi Sabri Muda, Nora Dato’ Yahya, Hasril Hasini, Ng Yu Jin & Fatin Faiqa Norkhairi
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-20
Residents living downstream of Kenyir dam (Stesen Janaelektrik Sultan Mahmud) are at risk of being flooded due to overflow through spillway, or worst, dam breaks. The nearest community to Kenyir dam is Kampung Jenagor (Kampung Jenagor) residents. A disaster preparedness action plan was proposed to equip the residents with essential knowledge on how to respond to such disaster and how to safely evacuate to designated safe havens. This paper presents one key element of the mentioned action plan, which is to develop and install a flood disaster early warning system. The system is aimed to effectively disseminate warning to Kampung Jenagor residents and ensure that there is a constant state of preparedness. The paper discusses the fundamentals of effective warning dissemination and basic design of Kampung Jenagor’s early warning system.
Keywords: Disaster preparedness; early warning system
Maidiana Othman*, Zuliziana Suif , Nordila Ahmad, Siti Khadijah Che Osmi & Mohamad Nazrul Hafiz Mohd Nadzri
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-21
Water scarcity and storm water management are two major challenges that effect the ecosystem and urban environment. In hot and humid country such as Malaysia, wastewater reuse should be encouraging whenever it is safe and economically feasible. Constructed wetlands (CW) have been recognized as one of the environmentally friendly technologies and successfully used for treating a diverse range of wastewaters. Constructed wetland can also be suitable habitat for native wetland plants and associated fauna. In an urban setting such as a university campus, a constructed wetland can also be landscaped as an educational and attractive green space, providing service learning and teaching opportunities for campus and surround community members. This study examines the performance of pilot-scale constructed wetlands as a sustainable wastewater treatment in Universiti Pertahanan Nasional Malaysia (UPNM) campus for treating and reusing the stormwater in the mini-reservoir. The pilot-scale of constructed wetlands have been designed and constructed in the laboratory using native wetland plant, the Cat-tail Typha Angustifolia. The pilot-scale of CW with vertical subsurface flow (VSF) system was able to remove all parameters better than horizontal subsurface flow (HSF) system. The highest percentage of removal of all parameters was at hydraulic retention time (HRT) of 5 hours and percentage of removal increased with an increase in HRT. The percentage of removal for total suspended solid (TSS), Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD), and Dissolved Oxygen (DO) approximately 84%, 71%, 68%, and 25%. Thus, the constructed wetland had the potential to increase the water quality level of stromwater in UPNM campus in order to support the sustainability and Green Campus environment campaign.
Keywords: Waste water; pembinaan wetland; waste water management; sustainablity; green campus campaign
Sibani Priyadarshini Mohanty, Syahrull Hi-Fi Syam Ahmad Jamil, Jailani Abdul Kadir, Mohd Salman Mohd Sabri & Fakroul Ridzuan Hashim*
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-22
An artificial neural network (ANN) is a network designed with adaptation to a computer system. The developed computer system will perform functions oriented to the way the brain works (neuron concept). This study is an extension to the study of the suitability of ANN to be applied in numbers of applications, especially in the field of medical engineering. ANN has been widely being used in medicine, ANN is widely applied in education, research, and even decision making. In this study, ANN will be trained for pre-testing to predict the cardiac abnormalities symptom based on selected reference parameters. This reference parameter is better known as the input parameter to the ANN to detect cardiac abnormalities, among which are the of the height of peak/wave (amplitude) and time occurrence of peak/wave (duration of time) extracted from the electrocardiogram (ECG) signal. A complete ECG complex contains a P peak, a QRS wave, and a T peak. For each P peak, QRS wave, and T peak, amplitude height and duration will be measured to serve as input parameters. This makes six parameters defined as inputs to the ANN. This study has used a Multilayer Perceptron (MLP) network as ANN structure by being trained using three different training algorithms namely Backpropagation (BP), Lavenberg Marquardt (LM) and Bayesian Regularization (BR). At the end of the study, it showed the MLP network which by BR training algorithm gave the highest accuracy prediction (94.04%), followed by LM (92.95%) and BP (88.77%). In this study all MLP networks were activated using the Tansig activation function.
Keywords: MLP network; ECG signal; cardiac abnormality; amplitude; duration; tansig activation function
Fadli Sirait, Hizrin Dayana Mohd Hidzir, Mohd Taufik Jusoh, Khairol Amali Ahmad & Fakroul Ridzuan Hashim*
DOI : dx.doi.org/10.17576/jkukm-2021-si4(2)-23
This paper presents a directional bow tie patch antenna for ground penetrating radar (GPR) applications. There are four proposed designs for this paper. Three of the antenna is designed by introducing Sierpinski gasket fractal concept on bow tie patch antenna. There is some modification on this design in order to create a new different fractal design that is applicable for GPR applications. The bow tie antenna performance is studied across 1 GHz to 4 GHz. The best return loss obtained for this paper is at 3.7 GHz where all four designs have its best performance. The comparison at 3.7 GHz of these four antenna designs presented in this paper.
Keywords: Ground penetrating radar; bow tie antenna; patch antenna; radiation pattern