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Published By Penerbit Utm Press

2180-3722, 0127-9696

2021 ◽  
Vol 84 (1) ◽  
pp. 249-262
Author(s):  
Anis Amirah Mohamad ◽  
Fadzilah Adibah Abdul Majid ◽  
Suvik Assaw ◽  
Fadhilah Zainal Abidin ◽  
Anis Fadhlina ◽  
...  

R-38TM is a traditional herbal supplement for treating arthritis-related conditions. High-performance liquid chromatography (HPLC) analysis was performed for identification and quantification of rosmarinic acid in the R-38TM water extract. The anti-arthritic potential of the R-38TM water extract was investigated by measuring the production of IL-6 and TNF-α in inflamed cells. Xanthine oxidase (XO) and cyclooxygenase-2 (COX-2) inhibition assays were also conducted. The cytotoxic effect of R-38TM water extract was investigated on HSF1184 cell line. Acute and subacute oral toxicity studies were conducted on female Sprague-Dawley (SD) rats. The rosmarinic acid was identified at 1.208 min (3.61 %w/w). The inflamed cells showed a decrease in the production of IL-6 (55.9%) and TNF-α (52.13%). The COX-2 and XO enzymes were moderately inhibited by R-38TM water extract. The cytotoxicity analysis showed no cytotoxic effect on the cell. The acute and subacute oral toxicity studies revealed no mortality and normal body weight at all doses. There were no significant differences (p > 0.05) in organ weight, hematological and biochemical parameters, and histology of liver and kidneys with the control group. In conclusion, R-38TM water extract exhibited no toxic effect orally and may possess potential therapeutic properties against pro-inflammatory diseases including arthritis.


2021 ◽  
Vol 84 (1) ◽  
pp. 241-247
Author(s):  
Loo Tung Lun ◽  
Tam Swee Chin ◽  
Mohamad Khairi Ishak ◽  
Mohd Shahrimie Mohd Asaari

The unprecedented outbreak of novel coronavirus 2019 (COVID-19) globally has a huge impact to our daily life in numerous ways. To effectively minimize the spread of the virus, early symptom detection is crucial, especially in closed environment with high human traffic areas which post higher chances of human-to-human transmission. Body temperature measurement has been identified among the vital monitoring parameters. However, current available temperature monitoring mechanism is costly, limited to single individual and limited to locally without integrating to cloud and database. This led to difficulty in effective surveillance for suspicious COVID cases. Hence, the purpose of this paper is to introduce an end-to-end Internet of Things-enabled application for thermal monitoring as an early signal detection and screening method. This work integrates Raspberry Pi, thermal sensor, LCD display, buzzer, and LED light with Raspbian and Restful API for device-to-cloud communication. The system implemented is capable for user identification, body temperature remote monitoring and warning signal for fever symptoms. The result of this real-time system is capable to detect and screen the suspected contagious person in an organization effectively. Future works on integrating face recognition with machine learning and artificial intelligent enhancement.


2021 ◽  
Vol 84 (1) ◽  
pp. 231-239
Author(s):  
Nitin Agarwal ◽  
Manish Gupta ◽  
Manish Kumar

In today’s world, radio receiver system is a prevailing wireless technology in that the major part is Low Noise Amplifier (LNA) which widely used to improve weak signals in many applications with millimeter and radio frequency waves such as optical communication, multimode transceivers and measurement instrumentations. The real drawbacks of LNA is that it fails to maintain specific properties in critical conditions like as minimum power consumption, provide low noise figure, input matching and linearity. Additionally, promoted by various application demands, design methods and control methods must require to improve performance of LNA. The performance of LNA can be improved by adding extra components in basic circuit by proper arrangement for millimeter and radio frequency waves. The review paper provides information about design methodology, optimization techniques and control techniques. The different design of LNA is reviewed and analyzed such as 3-stage near-mm Wave LNA, 5-stage near-mm Wave LNA, common-gate amplifier, shunt-feedback amplifier, Resistor-terminated common-source amplifier, Traditional inductor-less amplifiers, cascode connection and double common source. This review paper also provides the information about design circuit diagram. The performance improvement of LNA can be achieved with the help of different techniques and our review based on optimization and control techniques with parameter tuning. Finally, the direction for the future study is presented based on review analysis of LNA.


2021 ◽  
Vol 84 (1) ◽  
pp. 219-230
Author(s):  
S. N. Ishak ◽  
J. Sampe ◽  
Z. Yusoff ◽  
M. Faseehuddin

An all-digital phase locked loop (ADPLL)-based local oscillator (LO) of RF transceiver application such as radio-frequency identification (RFID) system has gained popularity by accessing the benefits in complementary metal-oxide semiconductor (CMOS) process technology. This paper reviews some state-of-art of the ADPLL structures based on their applications and analyses its major implementation block, which is the digital-controlled oscillator (DCO). The DCO is evaluated based on its CMOS scaling and its performance in ADPLL, such as the power consumption, the chip area, the frequency range, the supply voltage, and the phase noise. Based on the review, the reduction in CMOS scaling decreases the transistor size in ADPLL design which leads to a smaller area and a low power dissipation. The combination of the time-to-digital (TDC) and the digital-to-time converter (DTC) that is used as the phase-frequency detector (PFD) in ADPLL is proposed to reduce the power and phase noise performance due to their high linearity design. The delay cell oscillator is found to consume more power at higher operating frequency, but it has an advantage of having less complexity and consuming less power and area in the circuit compared to the LC tank oscillator. For future work, it is recommended that an ADPLL-based LO of RFID transceiver with lowest voltage supply implementation is chosen and the use of the TDC-less as the PFD is selected due to its small area. While for the DCO, the delay cell will be designed due to its simpler implementation and occupy small area.


2021 ◽  
Vol 84 (1) ◽  
pp. 211-218
Author(s):  
A Evi Susanti ◽  
Suharti Suharti ◽  
Roswanira Wahab ◽  
Naharotul Chusniyah ◽  
Shindy Tirta Paramitha

This research aimed to isolate protease-producing bacteria from Sidoarjo shrimp paste for extracting collagen from milkfish scales. This study began with isolation, followed by screening and purification of protease-producing bacterial isolates. Further confirmation of the isolates’ proteolytic indices and the crude protease production, the enzymes’ efficacy in extracting collagen from milkfish scales were tested, followed by pathogenicity and identification using 16S rRNA molecular technique. The study has successfully isolated 15 proteolytic bacterial isolates using skimmed milk agar, but only isolates of TR-10, TR-4.1.1, and TR-15.1 exhibited prospective proteolytic activity based on their corresponding proteolytic indices of 2.96 ± 0.06, 3.10 ± 0.10, and 3.71 ± 0.48. Although the proteolytic activity of isolates TR-10 (0.22 ± 0.05 U/mL) and TR-15.1 (1.07 ± 0.14 U/mL) was high in a salt medium using peptone as the nitrogen source, only the former showed satisfactory activity to extract soluble collagen from milkfish scales. Based on the 16SrRNA, the TR-10 isolate was identified as Bacillus megaterium. The non-pathogenicity of the TR-10 bacterium signified its promising role as a protease source for the halal collagen extraction from milkfish scales.


2021 ◽  
Vol 84 (1) ◽  
pp. 193-210
Author(s):  
Muhammad Roslan Rahim ◽  
Annisa Palupi Trisasongko ◽  
Mohammad Nazri Mohd Jaafar ◽  
Norazila Othman ◽  
Yahaya Ramli ◽  
...  

Gasification technologies have the potential to produce clean and efficient energy sources. This technology is capable of producing synthesis gas from low or negative carbon -based raw materials such as coal, petroleum coke, high sulfur fuel oil, waste or waste materials and biomass. The gas produced from the process is used to replace natural gas to generate electrical power, or acts as basic raw material for producing chemicals and liquid fuels. Gasification is a process which utilizes heat, pressure, and steam to convert materials directly into gases, such as carbon monoxide and hydrogen gases. Despite differing in various aspects, gasification technologies have four common engineering factors such as atmospheric gasification reactors (oxygen or air content level), internal and external heating, reactor design and operating temperature. Raw materials, either in dry form or small granules, are fed into the reactor chamber called gasifier. Raw materials subjected to heat, pressure as well as an environment with rich or low oxygen content. Hydrocarbon gas (also known as Syngas), liquid hydrocarbon (oil) and coal (carbon black and ash) are the three main products of gasification. Syngas can be used as a fuel to produce electricity or steam, or acts as a basic block for various types of chemicals. When mixed with air, Syngas can be used in petrol or diesel engines with slight modifications to the engine.


2021 ◽  
Vol 84 (1) ◽  
pp. 97-105
Author(s):  
S. Kavetha ◽  
A. S. Ja'afar ◽  
M. Z. A. Aziz ◽  
A. A. M. Isa ◽  
M. S. Johal ◽  
...  

LoRa is identified as Long-Range low power network technology for Low Power Wide Area Network (LPWAN) usage. Nowadays, Global Positioning System (GPS) is an important system which is used for location and navigation predominantly used in outdoor but less accurate in indoor environment. Most of LoRa technology have been used on the internet-of-things (ioT) but very few use it as localization system. In this project, a GPS-less solution is proposed where LoRa Positioning System was developed which consists of LoRa transmitter, LoRa transceiver and LoRa receiver. The system has been developed by collecting the RSSI which is then used for the distance estimation. Next, Kalman filter with certain model has been implemented to overcome the effect of multipath fading especially for indoor environment and the trilateration technique is applied to estimate the location of the user. Both distribution estimation results for Line-Of-Sight (LOS) and Non-Line-Of-Sight (NLOS) condition were analyzed. Then, the comparison RMSE achievement is analyzed between the trilateration and with the Kalman Filter. GPS position also were collected as comparison to the LoRa based positioning. Lastly, the Cumulative Density Function (CDF) shows 90% of the localization algorithm error for LOS is lower than 0.82 meters while for NLOS is 1.17 meters.


2021 ◽  
Vol 84 (1) ◽  
pp. 183-192
Author(s):  
Normazlianita Mohamad Alias ◽  
Zakiran Abd Razak ◽  
Munirah Janjori ◽  
Mohd Yazed Ahmad ◽  
Julia Patrick Engkasan ◽  
...  

Call bell systems play an essential role in patient and nurse interaction in hospitals and at homes. However, many hospitalized patients, especially patients with tetraplegia, cannot press a call bell button for assistance due to hand weakness or paralysis from the neck down. This problem has motivated developing a fabric-based multi-array pressure sensor as a call bell garment, named ePillow, that works by detecting the pressure pattern on a pillow surface where the patient is lying down. In this study, off-the-shelf materials were utilized to form: i) a fabric-based multi-array pressure sensor system, ii) an acquisition circuit along with an interface, and iii) a signal processing algorithm to acquire and interpret the sensor data. To ensure the functionality of the proposed ePillow, a color-coded mesh plot was developed to visualize the sensor data. The reliability of the system was tested with two individuals. The pressure profile of the proposed ePillow shows a comparable profile to that of the commercialized pressure sensor. Findings from this case study have demonstrated the ability to map the force on the surface of the pillow and subsequently the location of the force applied with 71% accuracy and 70% sensitivity.  


2021 ◽  
Vol 84 (1) ◽  
pp. 57-75
Author(s):  
Noraini Rosli ◽  
Geoffery James Gerusu ◽  
Roland Kueh Jui Heng

With rapid development in South East Asian countries, there is a risk of serious degradation of stream water quality in areas  adjacent to developing city areas, where basic information on toxic heavy metals and acidic compounds (NO3- and SO42-) concentrations and spatiotemporal variation is still unknown in these areas. The concentrations of water quality parameters, major ions, and heavy metals were examined from selected stream in a rehabilitation forest near a developing city having petroleum refinery facility in Bintulu, Sarawak, Malaysia. The concentrations of water quality parameters, major ions, and heavy metals were examined from twelve stream locations in a rehabilitation forest near a developing city with a  petroleum refinery facility. Analyses suggested that there is no clear tendency that is detected in  heavy metals and basic water properties (EC, DO, BOD, COD, alkalinity and pH) except for turbidity, total suspended solids,  and major ion which were high during rainy seasons. Annual means of SO42-, NO3- and NH₄⁺ concentrations were 6.34, 1.05 and 0.24 mg/L. The concentration in K+, Mg2+, Na+ and Ca2+ were 0.61, 1.21, 2.82 and 1.12 mg/L during hot and rainy season. The mean  concentration in almost all heavy metals (Mn, Fe, Cu, Zn) were less than 0.01 mg/L. The concentrations of water quality variables in all samples collected across the seasons except for turbidity found within the permissible limit by the WHO and NWQS for Malaysia. Rehabilitation forest might give a positive impact in preserving water quality especially for COD and major ions except SO42-.


2021 ◽  
Vol 84 (1) ◽  
pp. 77-83
Author(s):  
Mohamad Ikhwan Nordin ◽  
Jurifa Mat Lazi ◽  
Md Hairul Nizam Talib ◽  
Zulkifilie Ibrahim

In this paper, Sensorless Permanent Magnet Synchronous Motor (PMSM) using Extended Kalman Filter (EKF) is presented. The previous PMSM drive uses a sensor to measure the motor’s speed. Then the idea is to replace the sensor by using sensorless drives based on the observer. For the conventional observer, it’s only good for low current and low-speed applications. Moreover, it is hard to detect the phase voltage due to the non-existence of neutral wire. Therefore, this project proposes sensorless control using an EKF. This method provides an optional estimation algorithm for the non-linear system that can produce a fast and accurate estimation of state variables. The accurate estimation will reduce the noise and ripple of the system. Additionally, the EKF do not require the information of mechanical parameters and the initial position of the rotor, making the construction is easy and simple. In this paper, the fundamental of the EKF algorithm is explained and the simulation results for different speeds and loads are presented. The noise reduction test is also conducted to measure the flux current with and without the filter. The simulation study is achieved using MATLAB/Simulink to verify the effectiveness of the proposed method. The results of the simulation show that the sensorless PMSM drives using EKF have lower overshoot and faster rise time during start-up conditions and have lower undershoot during the loaded condition. It also can be concluded that the proposed sensorless PMSM drive using EKF has good speed control accuracy and can reduce the current noise.


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