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Articles by M. Ismail
Total Records ( 23 ) for M. Ismail
  S.E. Ghrare , M.A. Mohd. Ali , K. Jumari and M. Ismail
  Problem statement: Nowadays a large number of various medical images are generated from hospitals and medical centers with sophisticated image acquisition devices, the movement toward digital images in radiology presents the problem of how to conveniently and economically store, retrieve and transmit the volume of digital images. Thus digital image data compression is necessary in order to solve this problem. So in a wide range of medical applications such as disease diagnostic and during the compression process, the loss of information is unacceptable; hence medical images are required to be at high resolution as possible. Instead of lossy compression with relatively high compression ratio, mathematical lossless compression methods are favored in this field. Approach: In this study, an efficient new lossless image coding algorithm using a simple technique was presented. Our coding algorithm was based on pixel redundancy reduction by formulating two matrices only, which were Gray Scale Matrix (GSM) and Binary Matrix (BM). These matrices had been used for coding and decoding processes. Results: Results showed that the maximum compression ratio achieved using the proposed method was 4:1, which was more efficient than the present lossless techniques, moreover the computational complexity is greatly simplified; therefore producing very fast coding and decoding. Conclusion: This algorithm was most suitable for those images where lossy compression was avoided such as medical images used for teleradiology and other telemedicine purposed and it can be applied to other medical modalities.
  Norsuzila Y. , M. Abdullah and M. Ismail
  The signals from the satellites of the Navstar Global Positioning System (GPS) travel through the earth's ionosphere on their way to GPS receivers. However, ionospheric delay is one of the main sources of error in GPS. The magnitude of the ionospheric delay is influenced by the Total Electron Content (TEC) along the radio wave path from a GPS satellite to the ground receiver. This study investigates the TEC using GPS data collected from Wisma Tanah, Kuala Lumpur, KTPK (3° 10’ 15.44"N, 101° 43’ 03.35"E) station and processed and analyzed under quiet geomagnetic day at the equatorial region on 8 November 2005. This research assesses the errors translated from the code-delay to the carrier-phase ionospheric observable by the so-called leveling process, which was applied to reduce multipath from the data. It was found that the leveled carrier-phase ionosphere observable was affected by a systematic error, produced by code-delay multipath through the leveling procedure. The effects, however, do not cancel after averaging all the data. Dual frequency carrier-phase and code-delay GPS observations are combined to obtain ionospheric observable related to the slant TEC (TECs) along the satellite-receiver line of sight (los). This results in the absolute differential delay and the remaining noise was discarded. These are the first results obtained using TEC-GPS technique for TEC measurement in Malaysia.
  S. Shahbazi , K. Jumari and M. Ismail
  Problem statement: Real-time Transport Control Protocol (RTCP) protocol has been thesubject of various criticisms due its problematic performance in large-scale networks. S-RTCP is aprotocol with high potential as it has proved to be able to solve many problems of RTCP. It hasnumerous flaws on its own. This study aimed at dealing with flaws of S-RTCP and improving it interms of stability and packet loss.
Approach: A new proposed scheme was designed. Modificationsincluded designing multi-manager scheme, improving parent-seeking procedures, reducing distributionof request packets, reforming the design to be independent from TTL, adding methods to check on sanityof manager nodes. This study considered packet loss ratio of below 2% as desirable.
Results: ER-RTCPcomparing to legacy RTCP in terms of packet loss using NS-2 in four different scenarios revealedimprovements between 73 and 88% for various scenarios. It also kept packet loss rate below 2% for allscenarios. Comparison of ER-RTCP to S-RTCP showed that based on different α (stability of eachsingle manager) values, ER-RTCP was more stable as it showed more resistance to entire schemebreakdown (β). ER-RTCP's parent-seeking procedure, as modeled scenario revealed a packetgeneration reduction of 97%, compared to S-RTCP’s. In occurrence of parent AG leave or loss, ERRTCPreduced request packet generation by 95%. Allowance of AG dismissing in ER-RTCP, avoidedoccurrence of packet loss, as sample scenario showed S-RTCP experiencing packet loss of 3.5% whileER-RTCP kept packet loss at zero in theory.
Conclusion: Proposed design improved S-RTCP in termsof reduction of packet loss and stability.
  Omar M. Eshanta , M. Ismail , K. Jumari and P. Yahaya
  In IEEE 802.16, one of the main features is the QoS-Provisioning. The limited bandwidth and the increasing of the high data rate service users will impact the performance of the system. In this study, we propose a VHO algorithm that can support the provisioning of QoS in mobile WiMAX networks by handing over some Best-Effort (BE) low-speed WiMAX Subscriber Station (SS) to an overlaid WLAN network subject to the QoS guarantee for the SS. Our simulation results show that by utilizing the overlaid WLAN hotspots we can gain some free band for the new SS requests. According to our simulation results a significant improvement in the capacity and the probability of blocking (PB) in WiMAX network was achieved.
  Z.M. Hanapi , M. Ismail , K. Jumari , M. Mahdavi and H. Mirvaziri
  In this study, different collection window’s size is been analyzed to investigate the impact on network performance: packet delivery ratio, message overhead and end to end delay on the Dynamic Window Secured Implicit Geographic Forwarding (DWIGF) routing protocol where this protocol is based on a dynamic collection window approached. Its method on using dynamic window’s size has minimized the probability of selecting attackers and guaranteed high packet delivery ratios when there is a blackhole attack in the communication link. The DWSIGF is then compared with the best chosen window’s size to analyze the network performance with and without attacker in the communication line, respectively. The DWIGF is able to minimize a Clear To Send (CTS) rushing attack that leads to a blackhole and selectively forwarding attack with a guaranteed of high packet delivery ratios where a selection of a failed node and an attacker is minimized, respectively. As a result, this routing protocol is promising a dynamic and secured communication without inserting any existing security mechanism inside.
  M. Mahdavi , M. Ismail , K. Jumari and Z.M. Hanapi
  Sensing coverage and network connectivity are two main requirements which maintain perfect operation of wireless sensor network. Joint scheduling method has considered both requirements by using random scheduling for sensing coverage, which divides sensor nodes to k subsets. Each sensor nodes randomly selects one defined subset. Then, the algorithm turns on extra sensor nodes, if necessary for network connectivity. As Extra-on sensor nodes participate in other nodes routing, some of them may be subject of many times transmission and reception. Furthermore, some of Extra-on nodes should be active the whole time to create network connectivity. Both mentioned reasons can drain out energy of those extra active nodes and may lead to network partitioning. Hence, reducing number of Extra-on nodes is important. In this study, we utilize probing mechanism scheduling in joint scheduling method to reduce the number of extra on sensor nodes. By using probing mechanism that some nodes change their working schedule, number of extra on nodes reduces by 20%.
  A.L. Yusof , M. Ismail and N. Misran
  The objective of this research is to propose an adaptive handoff algorithm which can effectively deal with hotspot cells in next-generation cellular networks. Under the proposed algorithm, the signaling burden is evenly distributed and the regional network boundary is dynamically adjusted according to the traffic load, handoff type and speed of mobiles in advance, before handoff execution. A simulation model is developed to investigate the handoff performance. The simulation results find that the proposed algorithm is better than traditional handoff algorithm. Therefore, this algorithm enhances the service quality of users by flexibly manage the overloaded cells.
  S.A. Farrag , A.B. Tanatarov , M.E. Soltan , M. Ismail and O.M. Zayed
  Three Japanese quail lines A-C were examined genetically using 13 micro-satellite markers to detect genetic diversity. The studied loci on average produced 5 alleles locus•1 (range: 2-8). The mean observed Heterozygosity (Ho) was 0.609 and ranged across loci from 0.00-0.967 whereas the mean expected Heterozygosity (He) was 0.636 and ranged between 0.139 and 0.802. The Polymorphic Information Content (PIC) values varied among loci and ranged between 0.346 for locus GUJ0010 and 0.814 for locus GUJ0087 with overall mean 0.644. Differentiation among populations was moderate but highly significant (FST = 0.10, RST = 0.17; p<0.0001) however, within populations differentiation accounted for 3.61 and -0.73% of the total nuclear microsatellite variation under Infinite Allele Model (IAM) and Stepwise Mutation model (SSM), respectively. Cluster analysis based on Nei’s genetic distance indicated that the studied populations formed two main groups. The 1st group included line A and the 2nd group harboured lines B and C. These results reflect that the set of studied markers can be used effectively to capture the magnitude of genetic variability in different Japanese quail populations.
  A.Y. Al-Taher , M.K. Zabady , A.I. Almubarak , M. Ismail and R.O. Ramadan
  This study was conducted to evaluate the analgesic and sedative efficacy of the combination of tramadol-xylazine used in six dromedary camels underwent soft tissue surgeries and premidicated with Intravenous (IV) 0.2 mg kg-1 of xylazine. The combination was induced IV with 2.0 mg kg-1 of tramadol and 0.2 mg kg-1 of xylazine, IV top-up of the combination of the same original doses was injected whenever the analgesia was inadequate or when surgical stimulation provoked movement. A surgically satisfactory analgesia was achieved and maintained in all camels by this combination except in two camels that underwent perineal laceration and castration showing signs of distress and pain as the injection dose was insufficient even after a supplemental dose at the same original dose was administered. Mean time±SD from administration of the combination of tramadol-xylazine until end of operation was 39.5±10.1 min. This study concludes that the combination of tramadol-xyalzine was effective and safe to use in camels and suggests that combination can be improved upon by combining with local analgesic drug to achieve adequate depth of analgesia.
  K. Singh , M. Ismail , K. Jumari , M. Abdullah and K. Mat

This study presents the development of techniques to estimate mobile user`s location (position) for Universal Intelligent Positioning System (UIPS) project. UIPS uses combination of available Location Determining Technologies (LDT) and newly developed techniques for UMTS (3G) or beyond networks. The usage of each LDT (technique) will determine Location Base Services QoS (accuracy of mobile user`s location). The new techniques developed are Close Circle Correlation (CCC) and Newton Raphsons 3 Circles (NR3C). Both techniques use time measurements observed from three Node B (base stations) in known Line of Sight (LOS) environment (multipath time delays are known). For unknown LOS environment, further enhancements on CCC technique and NR3C technique are developed, such as Averaging Estimator of CCC, First Mean Averaging Estimator of NR3C and Random Search Averaging Estimator of NR3C. The Cumulative Distribution Function of simulated results (simulation of actual data collected through drive test in UMTS network with known LOS) using NR3C technique produced 67% of the estimated user`s location error at 0 m and 95% of the estimated location error at 1.7 nm. Using CCC technique, produced 67% estimated location error at 2.04 m and 95% estimated location error at 3.2 m. NR3C produces better accuracy in known conditions of multipath delays. In unknown LOS conditions, Averaging Estimator of CCC produced 67% location error at 50.67 m and 95% error at 218 m, which is better than the other two enhanced (averaging) techniques of NR3C.

  A. Saad , M. Ismail and N. Misran
  This research aims to study the effect of Channel State Information (CSI) at the transmitter on the overall channel capacity. The capacity of MIMO correlated Rayleigh channels for different antenna configurations with and without channel knowledge (CSI) at the transmitter is simulated. When CSI is available at the transmitter (i.e., informed transmitter), waterfilling algorithm is used to allocate the power among the transmitter antennas. Simulations show that capacity is improved significantly when CSI is known at the transmitter. It also shows that the lack in channel knowledge (i.e., uninformed transmitter) can be compensated for by increasing the number of antennas in the receiver (Mr). When the number of antennas in the transmitter is larger than those in the receiver, using waterfilling becomes necessary to get the optimum capacity.
  F. Sayadi , M. Ismail , N. Misran and K. Jumari
  In this study, tunnels radio coverage utilizing leaky coaxial cable has been described. This cable can be deployed as a base station antenna for indoor wireless system such as tunnels. The older type of leaky cables is called coupled mode, while latest type is called radiation mode. These two modes can be distinguished by their radiation pattern, method of radiation (i.e., wave or energy) and class of slot on outer conductor. To obtain the field radiation patterns, we use two models; diffuse and deterministic models. Then a modified ray tracing algorithm has been used and simulated to predict radio coverage in tunnels by leaky cable deployment. Simulations show that leaky cables achieve better RF coverage than distributed antennas in term of received signal level versus frequency for various lengths and cross section of tunnels.
  A.N. H. Alnuaimy , M. Ismail , M.A. M. Ali and K. Jumari
  In an improved algorithm of channel estimations of Orthogonal Frequency Division Multiplexing (OFDM) system based pilot signal, the channel will be estimated using the mean and the variance of the two adjusted channel samples which have been extracted from that those embedded pilot signal in given positions of the frequency-time grid of OFDM signals. In this study, we present the application of Trellis Code Modulation (TCM) over an improved algorithm of the of the channel estimation of OFDM system based pilot signal and the usage of wavelet de-noising filter for that estimated channel sample to reduce the noise which affect the estimation of the channel. Simulation results shows that the combination of the TCM and the Wavelet de-noising filter will increase the performance of the OFDM system over that improved algorithm for the channel estimations.
  Yasin M. Karfaa , M. Ismail , F.M. Abbou , S. Shaari and S.P. Majumder
  A semi analytical analysis is carried out to investigate the effect of linear crosstalk due to wavelength converters and other Wavelength Division Multiplexing (WDM) components in the presence of interferometric intensity noise and amplified spontaneous emission on the performance of an optical multi-wavelength transport network employing wavelength converters based on XPM in a Single Mode Fiber (SMF) and Mach-Zehnder Interferometer (MZI), where a new parameter names Relative Output Noise (RON) is identified and accounted for. Theoretical study is done for the Bit Error Rate (BER) performance analysis due to crosstalk and ASE noise. It is found that linear crosstalk induces higher penalty when the number of transmitted channels is increased in the presence of all the above effects. The conditions for conversion at 10 Gbps or more are identified. The initial results for monolithic integrated interferometric wavelength converters are reviewed by transmission of 10 Gb/s converted signals over non-dispersion shifted single mode fiber.
  R. Sari , Z. Yaakob , M. Ismail and W.R.W. Daud
  In this study, the potential of utilizing the porous alumina ceramic membrane coated with palladium as a hydrogen permselective membrane has been studied. The ceramic membrane is characterized by high permeability but at low hydrogen selectivity. In order to increase the pure hydrogen selectivity and to obtain high hydrogen yield on the ceramic membrane, palladium was coated on the alumina membrane surface. Such an arrangement would also enable the ceramic membrane to be operated at higher temperature. The preparation of the palladium coated ceramic membrane was carried out using combine sol-gel process and the electroless plating technique. The effect of combine sol-gel process with electroless plating towards hydrogen permeation and hydrogen permselectivity were analysed. The thickness of the α-Alumina and Palladium composite membranes were analysed using a Scanning Electron Microscopy (SEM). The resulting membrane showed significantly higher hydrogen permeation but the same time decrease hydrogen permeability and permselectivity.
  W.N.R.W. Isahak , M. Ismail , M.A. Yarmo , J.M. Jahim and J. Salimon
  Crude glycerol samples used in this study consisted of crude glycerol (CG1) produced from homogeneous catalyst (NaOH) obtained from Golden Hope biodiesel plant and crude glycerol (CG2) as a product of heterogeneous catalysed transesterification RBD palm oil using KOH/Al2O3 catalyst. KOH/Al2O3 catalyst was produced by wet impregnation method and characterized by using BET, XRD and SEM-EDX methods. 15% KOH/ Al2O3 has BET surface area of 26.1 m2 g-1 compared with 100.4 m2 g-1 for fresh Al2O3. The first purification stage of the crude glycerol was achieved by employing the neutralization method followed by microfiltration and ion exchange resins methods. Inorganic salts as a result of the neutralization with 85% v/v phosphoric acid were filtered using syringe filter 0.45 μm. Only glycerol peak could be detected using a Dionex C-18 column in the HPLC indicating that the neutralization step enabled the removal of excess homogeneous catalyst as well as the unreacted free fatty acids in the crude glycerol samples. The free ions from salt and catalyst were then eliminated through ion exchange process using Amberlite resins to produce higher glycerol purity. The samples were also analyzed using FTIR to check on their purity level and to detect any impurity that may still exist. The products of this 3-step purification method were deemed comparable to that of a commercial pure glycerol based on the viscosity, pH value, free fatty acid value, moisture content and density rendering them as competitive feedstock for the biolubricant production.
  M. Salem , M. Ismail and N. Misran
  The indoor wireless environments suffer from the coverage disconnection. The trends in the future wireless networks are to enable the mobile terminal to be connected anytime and anywhere. An efficient location management will solve the problem of frequent location registration in the small area of indoor environment. This study treats the problem by developing an indoor location registration with sequential paging algorithm for future heterogeneous wireless networks. The algorithm is based on the RSS signal that received from the surrounding sources. The proposed algorithm has been compared with conventional registration with blanket paging algorithm in terms of the performed location registration and paging messages.
  K. Singh , S. Sulaiman , M. Ismail and K. Jumari
  In this study, a Location Determining Technique (LDT) to determine the approximate position of a cellular mobile user in a suburban environment is presented. This LDT uses Signal Correlation Method (SCM) where the Received Signal Strength (RSS) of one Node B is used to approximate the location of the 3G data user in a suburban environment. A new training technique called Unique Sample Undefined Collection (USUC) is introduced for SCM which uses Neural Network to match the current RSS with stored signal strength of Node Bs detected around the User Equipment (UE). With this new technique, the Cumulative Distribution Function (CDF) for location estimation at 67% error distance between the simulated samples and the actual positions of UE was significantly reduced from 379 to 107.4 m, while at 95% of the simulated samples, the error distance remains approximately the same, at 379 m. SCM-USUC may not be suitable for emergency location search but should be utilized by Universal Intelligent Positioning System (UIPS) for tracking location of UE when data or voice services are used especially in larger cell areas, such as in suburban environment.
  A.M. Fuah , R. Priyanto , S. Suharti , K.G. Wiryawan and M. Ismail
  The main problems behind low productivity of beef cattle raised by farmers in the villages are the less sufficiency of feed resources and low quality of feed available for the animals, especially the deficiency of protein/nitrogen and low feed intake. This study was aimed to improve the productivity of local cattle in Indonesia through the utilization of soybean meal and its wastes as the main protein source. Twelve heads of Madura cattle with an average initial live weight of 175.64±16.4 kg and ages between I1-I2 (18-30 months) were used in the study. The cattle were allotted into four feeding treatments i.e., T0 as control (100% native grass); T1 (40% roughage 60% concentrate); T2 (complete feed with 15% soybean pods) and T3 (complete feed with 30% soybean pods, for three months. The observed parameters included cattle performance (final weight, average daily gain, feed consumption and feed conversion), carcass quality (backfat thickness, loin eye area and meat color) and physical quality of meat (pH, water holding capacity, cooking loss and meat tenderness). The results showed that cattle fed soybean wastes (T1, T2 and T3) were higher in all variables of cattle performance and backfat thickness compared to those fed control feed. Utilization of feed combined with soybean waste could improve cattle performance with relatively better meat quality than those given grass only.
  R. Priyanto , A.M. Fuah , S. Suharti , I.K.G. Wiryawan , M. Ismail and D. Firmansyah
  Background and Objective: The objective of this study was to evaluate the growth performance of Ongole Crossbreed (PO) cattle fed soybean by-products as a substitution for roughage. Methodology: Twenty PO cattle at 1.5 years of age were used in this study and were given 4 feeding treatments (T1:70% concentrate without tofu waste and 30% grass, T2:70% concentrate containing tofu waste, 15% grass and 15% soybean pods, T3:70% concentrate containing tofu waste and 30% soybean pods and T4:70% concentrate containing tofu waste and 3-0% fermented soybean pods). Each treatment was applied to 5 animals as a replication. The average crude protein content and Total Digestible Nutrients (TDN) of each feed combination were 14 and 70%, respectively. The parameters measured were as follows: (1) Average daily gain, (2) Dry matter intake, (3) Feed efficiency and (4) Rumen characteristics (i.e., rumen microbes, nitrogen retention, protozoa, allantoin and microbial protein synthesis). Results: The results indicate that cattle given 70% concentrate containing tofu waste with 30% fermented soybean pods (T4) performed well in terms of final body weight, average daily gain, dry matter intake and feed efficiency compared to the other treatments. At the end of the experiment, cattle that received T4 had a higher (p<0.05) final body weight compared to those that received the other treatments. Additionally, cattle fed 70% concentrate containing tofu waste with 30% fermented soybean pods showed a steady increase in average daily gain and showed better performance relative to those that received the other treatments. Cattle fed 70% concentrate containing tofu waste, 15% grass and 15% soybean pods and 70% concentrate containing tofu waste with 30% fermented soybean pods had higher dry matter intake compared to those that received the other treatments. The average feed efficiency of cattle fed T1 during phase 1 was higher than T2, T3 and T4, which was closely related to the average daily gain and dry matter intake. Along with the increased live weight, there was a significant change in average daily gain, which increased significantly in phase 2 and decreased in phase 3. Significant compensatory growth was observed during phase 2, cattle showed optimum growth, which was indicated by a significant increase in the average daily gain at 0.52-1.55, 0.85-1.31 and 1.09-1.41 kg day–1 in cattle fed T2, T3 and T4, respectively. During phase 3, the average daily gain of cattle of all feeding treatments decreased by 0.51 kg day–1 (T1), 0.93 kg day–1 (T2), 0.50 kg day–1 (T3) and 0.75 kg day–1 (T4). Based on the waste production analysis, the carrying capacity of soybean waste for cattle production was approximately 8 AU ha–1. Conclusion: Overall, this study suggested that the combination of 70% concentrate containing tofu waste with 30% fermented soybean pods resulted in a better performance of Ongole Crossbreed (PO) cattle, especially in final body weight, average daily gain and feed efficiency. Rumen characteristics of cattle fed all feeding treatments showed similar results, meaning that the conditions of the rumen were not significantly influenced by feeding treatment.
  R. Priyanto , H. Nuraini , Muladno , M. Ismail and H. Wijayanto
  Background and Objectives: Local cattle and buffalo slaughtered in public abattoirs vary widely in body fatness and live weight. The study was aimed to characterise carcass and non-carcass parameters of local cattle and buffalo differing in breed, sex and body fatness score using a carcass dressing procedure based on the national standard carcass definition. Methodology: A total of 291 cattle and buffalo were slaughtered at 20 public abattoirs from ten provinces of Indonesia. The slaughtered animals were classified according to breed (Bali, Madura, PO, local crossbred cattle, PFH and buffalo), body fatness score (very thin, thin, medium, fat and very fat) and sex (male and female). Results: The results indicated that the local cattle and buffalo slaughtered at public abattoirs were dominated by local crossbred cattle (59%), followed by Bali cattle (14%), PFH cattle (10%), PO cattle (8%), Madura cattle (7%) and swamp buffalo (2%). The animals were mainly in medium (49%) and poor (36%) conditions, while only 15% of the animals were in fat condition. Variations due to breed, age, sex and body fatness score were observed in slaughter weight, carcass and non-carcass characteristics. Conclusion: Overall, the majority of local cattle and buffalo of various breeds, ages and sexes slaughtered at public abattoirs in Indonesia had low to medium carcass productivity, which could be improved by increasing their body fatness score.
  Wafaa A. Abd El-Ghany and M. Ismail
  This study was designed to compare between the efficacy of a phytobiotic containing a mixture of essential oils of Oreganum aetheroleum and an antibiotic containing ciprofloxacin as an active principle for the treatment of experimental (E. coli) infection in broiler chickens. Two hundred, day old broiler chickens were divided into 5 equal groups. The 1st group was neither challenged nor treated but groups 2, 3, 4 and 5 were challenged with E. coli. The 2nd group was challenged only while the 3rd, 4th and 5th group were treated with phytobiotic, ciprofloxacin and phytobiotic and ciprofloxacin combination, respectively. Results confirmed significant (p<0.05) improvement of productive performance parameters, reduction in signs, mortalities, post mortem lesions and bacterial re-isolation, significant (p<0.05) enhancement in cell mediated and humoral immune responses, significant (p<0.05) reduction in levels of liver and kidney function tests as well as significant (p<0.05) increase in the total protein and globulin levels in chickens challenged with E. coli and treated with either essential oils or ciprofloxacin compared with challenged non treated chickens. Moreover, the best significant (p<0.05) results in all measured parameters were detected in group treated with combination in comparison with those treated with single treatment. In conclusion, a mixture of essential oils of Oreganum aetheroleum is effective for the treatment of E. coli infection in broiler chickens when compared with ciprofloxacin. However, combined treatment could be superior in controlling such infection of broiler chickens.
  W.N.R.W. Isahak , M. Ismail , J. Mohd Jahim , J. Salimon and M.A. Yarmo
  In this study, the transesterification reaction was performed using choline chloride: metal chloride salts and ionic liquids as the catalyst. The objectives of this study were consisted of synthesis, characterization and catalytic study of the choline chloride type ionic liquids as a catalyst. It was conducted based on four parameters, namely methanol to oil molar ratio, catalyst weight percent, amount of acid in ionic liquids and type of catalyst at 65°C for 4 h. The ionic liquids catalysts were characterized by using H1NMR and FTIR. The optimum condition for the reaction of choline chloride.ZnCl5¯ catalyst with 2.5 wt% catalyst, 20% amount of H2SO4 in ionic liquids which produced 92% of methyl ester. At the same condition, choline chloride.FeCl7¯ catalyst was produced 89.5% of methyl ester. A choline chloride type ionic liquid was cheaper, ease in preparation and separation compared to others without any complex methods. It can be separated by common technique such as freezing and centrifugation. The catalyst can be use until at least four times without any significant loss of products.
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