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Mohd Sani Mohamad Hashim
Preferred name
Mohd Sani Mohamad Hashim
Official Name
Mohd Sani , Mohamad Hashim
Alternative Name
Hashim, Mohd Sani Mohamad
Mohamad Hashim, M. S.
Hashim, M. S.M.
Hashim, Sani
Main Affiliation
Scopus Author ID
55638811600
Researcher ID
ABA-7717-2020
Now showing
1 - 10 of 31
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PublicationEfficiency analysis of a passive daylighting system based on Northern Malaysia’s climate(Semarak Ilmu Publishing, 2025-04)
; ;Muhammad Amin Zulkifli Din ; ; ; ;Ng Yi Fei ; ;Daylighting design strategy is important in order to have adequate lighting source in a room and necessary to decrease energy consumption for artificial lighting. Passive daylighting system utilizes daylight by collecting, reflecting and diffusing the natural light throughout a given area. The purpose for this study is to monitor, compare and analyse an optimum light pipe system design that can scatter daylight into a room based on three case studies. Lighting analysis was conducted using Autodesk 3ds Max Design software throughout the project based on the actual geographical parameters of Universiti Malaysia Perlis, Malaysia and also using the real sun azimuth on working hours. The results were compared according to the respective designs in order to observe the maximum internal illuminance and the average internal illuminance. The results show that the straight geometry with low aspect ratio produces the highest interior light intensity among other light pipe systems and the average internal illuminance values in the room was able to reach the minimum requirement of a small room which is 200 – 500 lux. -
PublicationAnalysis of WiFi Spatio-Temporal Data for Organic Fingerprinting-based Indoor Positioning System( 2022-01-01)
; ;Amirah Husna Mohd Hajazi ; ; ;The mobile robot navigation is the next huge topic after positioning utilizing fingerprinting-based Wireless Positioning System (WPS). Many of recent works does not discuss this topic yet since many open problems in positioning topic are not yet solved, for instance the issues on multi-devices heterogeneity, instability of WiFi signals, granularity problems in grid-based indoor environment and many others. However, we anticipate that both positioning and navigation works must run in parallel so that the succession are guaranteed. This paper describes the analysis of spatio-temporal data of the signal obtained from the WiFi Access Point. Initial results suggest that the difference between transmitter heights have an effect on the spatio-temporal data while the handover of maximum signal strengths is inherent when three WiFi APs are used.1 -
PublicationImprovement of Dissolved Oxygen in Perlis River based on Various Aeration Systems( 2021-12-14)
;Muhammad Faiz Hilmi Rani ; ; ; ; ; ; ; ;Ibrahim Z. ; ;Mohamad Aniq Syazwan Mohamed Hassan ;Abd Manap A.A.Zainuddin I.F.Water pollution is closely related to the Water Quality Index (WQI). One of the parameters in classifying WQI is dissolved oxygen (DO) that can be improved by introducing the surface and subsurface aerations. Herein, the Perlis River's water quality was investigated by evaluating the DO's improvement based on various aeration systems. The changes of DO (mg/L) and DO improvement (%) were evaluated during both low and high tide conditions. A total of 9 sets of data collection had been studied by comparing base DO (without running of aeration) and measured DO (with running of aeration) of river. The DO sensor was used to measure the changes of DO in the aeration measurement system. Results found that the DO improvement managed to achieve 74.89%, 10.18%, 35.58%, and 52.45% for water jet, air compressor, commercial venturi, and DIY venturi, respectively. Besides, different behaviour of DO's improvement was observed during low and high tide conditions.5 42 -
PublicationModeling on impact of metal object obstruction in urban environment for internet of things application in vehicular communication( 2020-01-08)
;Turner J.S.C. ; ; ; ; ;Fadzilla M.A. ; ; ;Razlan Z.M. ; ;Phoon C.Y.Objects such as vehicles are considered one of challenging obstruction on the road and very little attention has been made to address its significance on the wireless signal. As such, this paper validates the impact of vehicle obstruction on signal propagation using received signal strength indicator (RSSI) based on the wireless channel measurements of realistic environmental obstruction at 2.4 GHz frequency band. Low mobility IEEE 802.15.4 XBee S2C compliant device which is designed to collect received signal power was used and these devices were deployed at area congested with cars. The channel measurements were conducted on LOS car parking area with two scenarios; single-sided and double-sided vehicle obstruction which mimics the obstruction of metal objects. The effect of existing vehicle on the signal propagation is demonstrated based on RSSI and RMSE. The attenuation profile of vehicular obstruction on wireless signal is modeled and compared with large-scale propagation models. Results show that metal object significantly reduce transmission range and signal power. The findings may incite for future implementation of cooperative deployment program and internet of things (IoT) applications in vehicle-to-infrastructure (V2I) and vehicle-to-vehicle (V2V) communication.1 31 -
PublicationSignal propagation modelling for vehicle-to-infrastructure communication under the influence of metal obstruction( 2021-12)
;Jamie Siregar Cynthia Turner ; ; ; ; ;D L Ndzi ; ; ; ; ;M K N ZulkifliConnected car has become one of emerging technology in the automotive industries today. This development preludes a rise in vehicular communication studies that primarily targets radio channel modelling on vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communication mode. Considering vehicular obstruction, vast channel propagation studies have focused more on V2V mode while others consider the typical urban scenarios consisting of high traffic volumes of moving vehicles. Due to challenging propagation mechanisms and high complexity in such areas, radio propagation models applied in simulators assume an obstacle-free environment rather than considering the least effect imposed by metal obstruction on communication signal. Besides, there are limited studies pertaining to metal obstruction that considers several under-explored environments such as actual parking lots, junctions and other road infrastructure support. As such, this paper demonstrates signal attenuation analysis caused by the presence of metal objects in low density over obstacle-free environment on actual parking lot via V2I mode. Two scenarios such as LOS and NLOS conditions consisting of obstacle-free, cars and buses as static metal objects are evaluated. The aim of this research is to characterize signal strength caused by metal blockage on radio wave propagation predicated on the presence of vehicles as a subject of obstruction in comparison to obstacle-free vehicular environment. The validity of data is shown through received signal strength indicator (RSSI) and approximation analysis (RMSE) to demonstrate the efficiency of obtained measurements. The results demonstrated that Log-normal shadowing model yields the best fit to low-density metal obstruction scenario with smallest RMSE of 4.78 under bus obstruction whereas 5.72 under car obstruction.5 22 -
PublicationEngine Performance Analysis by Studying Heat Transfer in the Valve Seat through Steady-State Thermal Simulation( 2021-12-14)
;Mohamad Aniq Syazwan Mohamed Hassan ; ; ; ; ; ; ; ;Azizul Aziz I. ;Zunaidi Ibrahim ; ;Muhammad Faiz Hilmi Rani ; ;Rishan MuraliAs the engine reached high speed, the exhaust valve temperature increased exponentially due to the exhaust gas produced by the combustion process between the mixture of air and fuel within the combustion chamber of the internal combustion engine. The valve is subjected to thermal loading due to high temperature and pressure within the cylinder, which must withstand a material temperature for sustainable and optimal operation. To avoid this loss, a perfect medium must be prepared to ensure that the heat is extracted smoothly. This can be done when the valve is in contact with the seat and there is a periodic heat transfer contact. Therefore, it is imperative to research the correlation between valve and valve seat to understand the two sections' heat transfer mechanism. In this study, thermal contact analysis was used to identify heat transfer between the valve and the valve seat as both parts are interconnected. This research also has an interest in studying the two surface conduction mechanisms as the exhaust valve closed in steady-state conditions. Thus, this study portrays a significant method, particularly for the determining the distribution of temperature, heat flux, and heat flux direction between the valve and its seat using ANSYS Workbench.2 -
PublicationIntegration of asset tracking system through trilateration method as detection mechanism( 2019)
;M A Fadzilla ; ; ; ; ; ;Z. Ibrahim ; ;J.S.C Turner ;K.A.A Kassim ;M.S.A Khalid ;Z. Jawi ;M.H.M IsaDemands for localization system has been growing rapidly in the last several years both for an outdoor and indoor area. In conjunction with this, the capability and reliability of this system to precisely locate and track objects of interest for the indoor area has catered researchers and study on how to do so. One of the major ideas on making it more advance is by incorporating the use of wireless devices into the system. There are numbers of issues that could interrupt the efficiency and success of the system. One of the main problems is the signal loss mainly caused by the attenuation of the signal as they propagate through from the transmitter to the receiver. These attenuations are mostly due to the surface types the signal are traveling on and the objects that are in the Line of Sight in between the transmitter and receiver. In order to ensure the most reliable and efficient wireless connection between transmitter and receiver, a propagation study on the signal is needed for us to analyze and find the best way to trade off the signal attenuation based on the environment surrounding the system. By doing so, a thorough system that has models that can work efficiently even if we are to consider the attenuation factors. The system consists of nodes installed inside the research institute that acts as both transmitter and receivers. The transmitter and receiver will then process the signal that will then determine their location. The receiver is connected to the laptop in order to get a real-time reading so that we will be able to locate the transmitter. A networked of nodes are installed inside the research institute for experiment and the layout of the research is conferred for future references. Data from the experiment are then analyzed and a model for the signal propagation alongside the research institute is created. This model will be able to apprehend the signal attenuation despite the surrounding environment such as furniture and walls. A completed asset tracking system with models of signal attenuation will be built in the future for a more efficient signal transmission.41 2 -
PublicationCFD Simulation on Improving Water Quality based on Various Aerator Models to Demonstrate Cost Performance Analysis( 2021-12-14)
;Nazrul Najmi Norbashah ;Muhammad Faiz Hilmi Rani ; ; ; ; ; ; ; ;Ibrahim Z. ; ;Mohamad Aniq Syazwan Mohamed Hassan ;Abd Manap A.A.Zainuddin I.F.There are many types of aerator that can be used to perform a water treatment process either from air to water or from water to air approaches. Other than focusing on the performance itself, the usage cost of aerator should be forecasted in detail too to have a sustainable and economical method in remediating the polluted water. Therein, the cost performance analysis was demonstrated by performing a computational fluid dynamics (CFD) simulation on improving water quality based on various aerator models. The simulation was focused in a small-scale aeration tank that consists of a mixing chamber, air duct, and a few of bubble diffusers. The improvement of water quality was assessed by calculating the number of gas bubble particles produced by 4 different configurations of aerator model, namely aerator model A, B, C and D, respectively. Results found that the aerator model D (5 bubble diffuser at 620 L/min) produces the highest number of gas particles up to 72.2%. However, the aerator model C (5 bubble diffuser at 300 L/min) was found to achieve the most efficient and sustainable approach based on energy consuming and cost of aerator configuration when compared to the other aerator models.3 37 -
PublicationEffect of Sample Sizes in Fingerprinting Database for Wi-Fi System( 2021-01-01)
;Sa’ahiry A.H.A. ; ; ; ; ;Toyoura M.Indoor positioning system has been an essential work to substitute the Global Positioning System (GPS). GPS utilizing Global Navigation Satellite Systems (GNSS) cannot provide an accurate positioning in the indoor due to the multipath effect and shadow fading. Fingerprinting method with Wi-Fi technology is a promising system to solve this issue. However, there are several problems with the fingerprinting method. The fingerprinting database collected has different sample sizes where the previous researcher does not indicate any standard for the sample size to be used. In this paper, the effect of the sample sizes in fingerprinting database for Wi-Fi technology has been discussed deeply. The statistical analyzation for different sample sizes has been analyzed. Furthermore, two methods which are K- Nearest Neighbor (KNN) and Deep Neural Network (DNN) are being used to examine the effect of the sample sizes in term of accuracy and distance error. The discussion in this paper will contribute to the better sample size selection depending on the method taken by the user. The result shows that sample sizes are an important metrics in developing the indoor positioning system as it effects the result of the location estimation.1 38 -
PublicationDevelopment of a Novel Aeration Measurement System to Evaluate Water Treatment Process in a River( 2021-12-14)
;Muhammad Faiz Hilmi Rani ; ; ; ; ; ; ; ;Ibrahim Z. ; ;Mohamad Aniq Syazwan Mohamed Hassan ;Abd Manap A.A.Zainuddin I.F.A novel aeration measurement system was developed to evaluate the water treatment process in a river to acquire a more comparable dissolved oxygen value even if various types of aerations are tested. The system comprises of DO sensor, water flowmeter, anemometer, PVC pipes, water pump, air compressor pump, and truck tyre tubes. The PVC pipes consisting of a main drainage hole, 5 holes for dissolve oxygen data collection, 1 hole as the location of aerator system, and connectors were designed as the major part of the system by using Computer Aided Design software. The main drainage hole (horizontal pipe) was designed to be 288.5 cm in length, while the measured holes (vertical pipes) were designed to be 45.7 cm in height. By considering a systematic approach, the designed system is hopefully able to solve measuring issue of dissolved oxygen in moving water and to provide a better evaluation of water treatment process.1 34