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  1. Mawarnis ER, Ali Umar A, Tomitori M, Balouch A, Nurdin M, Muzakkar MZ, et al.
    ACS Omega, 2018 Sep 30;3(9):11526-11536.
    PMID: 31459253 DOI: 10.1021/acsomega.8b01268
    A combinative effect of two or more individual material properties, such as lattice parameters and chemical properties, has been well-known to generate novel nanomaterials with special crystal growth behavior and physico-chemical performance. This paper reports unusually high catalytic performance of AgPt nanoferns in the hydrogenation reaction of acetone conversion to isopropanol, which is several orders higher compared to the performance shown by pristine Pt nanocatalysts or other metals and metal-metal oxide hybrid catalyst systems. It has been demonstrated that the combinative effect during the bimetallisation of Ag and Pt produced nanostructures with a highly anisotropic morphology, i.e., hierarchical nanofern structures, which provide high-density active sites on the catalyst surface for an efficient catalytic reaction. The extent of the effect of structural growth on the catalytic performance of hierarchical AgPt nanoferns is discussed.
  2. Rasheed F, Zafar Z, Waseem ZA, Rafay M, Abdullah M, Salam MMA, et al.
    Int J Phytoremediation, 2020;22(3):287-294.
    PMID: 31468990 DOI: 10.1080/15226514.2019.1658711
    Conocarpus lancifolius is a fast-growing and drought tolerant tree species with phytoremediation potential in arid environments. The present study was conducted to evaluate the phytoaccumulation potential under wastewater treatment. The experiment was performed in a greenhouse where 3-month-old seedlings were irrigated with industrial wastewater and growth, biomass and physiological parameters were measured. Concentrations of zinc (Zn), lead (Pb), and cadmium (Cd) in leaves, shoots, and roots along with translocation and tolerance index were also determined. The results showed that under wastewater treatment total biomass increased from 24.2 to 31.5 g, net CO2 assimilation rate increased from 9.93 to 13.3 μmol m-2 s-1, and water use efficiency increased from 1.7 to 2.42. Similarly, heavy metals (Zn, Pb, and Cd) accumulation in stem, leaves, and roots increased significantly under wastewater treatment where the highest concentration of Zn, Pb and Cd was found in roots followed by leaves and stem, respectively. Tolerance index was found >1, and translocation factor of all heavy metals was found >1. The study revealed that phytoaccumulation potential of C. lancifolius was mainly driven by improved net CO2 assimilation rate and water use efficiency.
  3. Nur Aiman Suparlan, Muhammad Azrul Ku Ayob, Siti Hawa Hamzah, Hazrina Ahmad, Mohd Hisbany Mohd Hashim
    Scientific Research Journal, 2018;15(1):31-45.
    MyJurnal
    A ribbed slab structure has the advantage in the reduction of concrete volume in between the ribs resulting in a lower structural self-weight. In order to overcome the drawbacks in the construction process, the application of steel fibre self-compacting concrete (SCFRC) is seen as an alternative material to be used in the slab. This preliminary investigation was carried out to investigate the flexural behaviour of steel fibre selfcompacting concrete (SCFRC) asthe main material in ribbed slab omitting the conventionalreinforcements. Two samples ofribbed slab were prepared for this preliminary study; 2-ribbed and 3-ribbed in 1 m width to identify the effect of the geometry to the slab’s flexural behaviour. The dimension of both samples is 2.5 m x 1 m with 150 mm thickness. The compressive strength of the mix is 48.6 MPa based on the cubes tested at 28 days. Load was applied to failure by using the four point bending test set-up with simple support condition. The result of the experiment recorded ultimate load carrying capacity at 30.68 kN for the 2-ribbed slab and 25.52 kN for 3-ribbed slab. From the results, the ultimate load of the 2-ribbed sample exceeds 3-ribbed by approximately 20%. This proved that even with lower concrete volume, the sample can still withstand an almost similar ultimate load. Cracks was also observed and recorded with the maximum crack width of 2 mm. It can be concluded that the steel fibres do have the potential to withstand flexural loadings. Steel fibre reduces macro-crack forming into micro-cracks and improves concrete ductility, as well as improvement in deflection. This shows that steel fibre reinforced self-compacting concrete is practical as it offers good concrete properties as well as it can be mixed, placed easier without compaction.
  4. Ahmad Fuad Ab Ghani, Azrin Ahmad, Nor Salim Muhammad, Reduan Mat Dan, Rustamreen Jenal
    MyJurnal
    This study describes the review on maintenance related issues during design and construction stage
    within construction industry. The paper highlights the causes and errors made during design and
    construction stage and their impact during the operation/production/occupancy stage as well as the
    maintenance costs associated with it. The study identifies the mistakes in the working processes within
    design and construction stage leading to the errors that affect the durability, performance, reliability,
    maintainability, availability and safety of the systems. The paper presents a comprehensive review of
    the published literatures, journals, technical papers in the related areas in the construction field. The
    review highlights the new approaches and decision framework which link the designers and
    construction personnel that could reduce the errors and defects in construction which then lead to
    maintenance issues and asset management. The factors of accessibility, materials, design and
    documentation standardization have been discussed thoroughly for better understanding in improving
    maintenance and physical asset management in project commissioning.
  5. B. Mabel Manjaji Matsumoto, Muhammad Ali Syed Hussein, Yee, Jean-Chai
    MyJurnal
    The central and north west coast of Sabah lies along the western extremity of the Coral Triangle, within which are situated several marine protected areas (MPAs). In the present study we determined in situ coral reef fish populations in several localities along the west coast of Sabah, by exploring species abundance, richness and diversity of ten economically important fish species. The underwater surveys were conducted from May to December 2015. During this eight- month period, surveys at each site were undertaken once every two months. Dives were conducted during the daylight hours. A total of 171 individuals from the targeted fish species were enumerated from the 349 still images and 220 minutes of video footage. Abundance was observed mainly in the semi-protected MPA (n=110) with only one fish species recorded with more than 2 individuals at protected MPA and unprotected sites. We observed a correlation between fish species richness and coral topographic complexity, with study sites at the semi-protected MPA having the most complex topography landscape, and accordingly recording the highest Shannon-Wiener index (H= 2.85). Higher abundance recorded at study sites in the unprotected sites and semi-protected MPA indicate that such areas could potentially become de facto MPAs. A long-term monitoring, assessment and evaluation of the multiple degrees of variables involved such as length-weight relationship, type of habitat, variation in depth, and species behaviour are recommended in order to understand better the relationship and dynamics between these variables.
  6. Anwar A, Shahbaz MS, Saad SM, Kanwal, Khan KM, Siddiqui R, et al.
    Eur J Med Chem, 2019 Nov 15;182:111575.
    PMID: 31415900 DOI: 10.1016/j.ejmech.2019.111575
    We report one-pot synthesis of a series of new 3-aryl-8-methylquinazolin-4(3H)-ones (QNZ) and their antimicrobial activity against Acanthamoeba castellanii belonging to T4 genotype. A library of fifteen synthetic derivatives of QNZs was synthesized, and their structural elucidation was performed by using nuclear magnetic resonance (NMR) spectroscopy and electron impact mass spectrometry (EI-MS). Elemental analyses and high-resolution mass spectrometry data of all derivatives were found to be in agreeable range. Amoebicidal assays performed at concentrations ranging from 50 to 100 μg/mL revealed that all derivatives of QNZ significantly decreased the viability of A. castellanii and QNZ 2, 5, 8, and 13 were found to have efficient antiamoebic effects. Field emission scanning electron microscopy (FESEM) imaging of amoeba treated with compounds 5 and 15 showed that these compounds cause structural alterations on the walls of A. castellanii. Furthermore, several QNZs inhibited the encystation and excystationas as well as abolished A. castellanii-mediated host cells cytopathogenicity in human cells. Whereas, these QNZs showed negligible cytotoxicity when tested against human cells in vitro. Hence, this study identified potential lead molecules having promising properties for drug development against A. castellanii. A brief structure-activity relationship is also developed to optimize the hit of most potent compounds from the library. To the best of our knowledge, it is first of its kind medicinal chemistry approach on a single class of compounds i.e., quinazolinone against keratitis and brain infection causing free-living amoeba, A. castellanii.
  7. Muhammad Khairul Anuar Mohamed, Nor Aida Zuraimi Md Noar, Mohd Zuki Salleh, Anuar Ishak
    Sains Malaysiana, 2016;45:189-296.
    In this paper, the problem of free convection boundary layer flow on a horizontal circular cylinder in a nanofluid with viscous dissipation and constant wall temperature is investigated. The transformed boundary layer equations are solved numerically using finite difference scheme namely the Keller-box method. Numerical solutions were obtained for the reduced skin friction coefficient, Nusselt number and Sherwood number as well as the velocity and temperature profiles.The features of the flow and heat transfer characteristics for various values of the Brownian motion parameter, thermophoresis parameter, Lewis number and Eckert number were analyzed and discussed.
  8. Nur Suhaili Abd Aziz, Muhammad Khairullah Nor Azmi, Abdul Manaf Hashim
    Sains Malaysiana, 2017;46:1083-1088.
    A one-pot green sonochemical process assisted by ascorbic acid as the reducing agent to produce highly reduced graphene oxide (rGO) decorated with silver nanoparticles (AgNPs) is demonstrated. A complete removal of oxygen-containing group in the GO sheets was confirmed by no observation of the peak corresponds to C-O, C=O and -OH bond. The unexpected decrease of peak intensity corresponds to sp2 hybridized C=C group is explained by a so-called bond polarity effect. The peak observed at ~400 nm seems to show the presence of AgNPs and the red shifting of C=C peak to ~270 nm after the introduction of ascorbic acid indicates the formation of highly reduced GO. The increase of AgNPs size and the crumpled silk-like morphology after the introduction of ascorbic acid also indicate the aggressive reduction of both AgNPs and GO. The increase of ID/IG ratio after the introduction of ascorbic acid seems to indicate the increase of the number of small sp2 domains, the presence of unrepaired defects and the restoration of the sp2 network. This work provides the promising green sonochemical approach by utilizing non-toxic and environmental-friendly reducing agent to produce highly reduced GO decorated with AgNPs for various applications.
  9. Siti Zubaidah Hasan, Zuhailie Zakaria, Mohamed Rozali Othman, Muhammad Rahimi Yusop
    Sains Malaysiana, 2018;47:1547-1556.
    Mangan oksida (MnO2
    ) poros nano yang mempunyai morfologi lapisan nipis telah disintesis dan diaplikasikan sebagai
    penjerap pewarna sintetik komersial (remazol merah, eriokrom hitam dan metilena biru). Permukaan bahan silika
    alumina yang telah diubah suai dengan 3-aminopropiltrietoksisilana (APTES) digunakan dalam proses sonokimia pada
    suhu bilik dengan kehadiran 0.1 M kalium permanganat (KMnO4
    ) untuk menghasilkan komposit silika alumina-MnO2
    .
    Penyingkiran templat dijalankan untuk mendapatkan MnO2
    tulen bersaiz nano. Spektrum FTIR menunjukkan kehadiran
    getaran MnO2
    dalam julat 400 - 600 cm-1 dan corak XRD menunjukkan kehadiran birnesit jenis MnO2
    . Isoterma jerapnyahjerap
    N2
    menunjukkan MnO2
    tulen memiliki liang yang bersifat mesoporos iaitu 34.8 Å (± 0.4), manakala luas
    permukaan MnO2
    ialah 252.8 m2
    /g. Penjerap MnO2
    lapisan nipis yang diperoleh menunjukkan kebolehan menjerap
    pewarna eriokrom hitam dan metilena biru masing-masingnya sehingga 54% dan 99% serta kapasiti penjerapan masingmasing
    ialah 0.0024 dan 0.0077 mmol/g. Kedua-dua isoterma penjerapan eriokrom hitam dan metilena biru oleh MnO2
    masing-masing menepati ciri-ciri Langmuir dan Temkin. Sementara itu data kinetik penjerapan eriokrom hitam dan
    metilena biru kedua-duanya memenuhi tertib pertama pseudo.
  10. Nurul Mujahidah Ahmad Khairuddin, Amalina Muhammad Afifi, Katayoon Kalantari, Nur Awanis Hashim, Shaza Eva Mohamad
    Sains Malaysiana, 2018;47:1311-1318.
    Chitosan/polyvinyl alcohol (Chitosan/PVA) blended film was prepared by direct blend process and solution casting methods.
    In order to reduce the swelling ratio and enhance the chemical and mechanical stability, Chitosan/PVA film was crosslinked
    with glutaraldehyde in order to produce Chitosan-g-PVA. Bovine serum albumin (BSA) was used as a model protein
    to incorporate into the Chitosan-g-PVA. The chemical structure and morphological characteristics of films were studied
    by FT-IR and scanning electron microscopy (SEM). Mechanical and physical properties of blended films such as tensile
    properties in the dry and wet states, water uptake and water contact angle measurement were characterized. Blending
    PVA and chitosan improved strength and flexibility of the films. Crosslinking with glutaraldehyde further improves the
    tensile strength and decrease the hydrophilicity of films. BSA immobilized on the Chitosan-g-PVA film was calculated as
    BSA encapsulation efficiency.
  11. Asif MK, Nambiar P, Ibrahim N, Al-Amery SM, Khan IM
    Leg Med (Tokyo), 2019 Jul;39:9-14.
    PMID: 31158731 DOI: 10.1016/j.legalmed.2019.05.003
    Three-dimensional imaging has improved the method of analysis in many forensic science investigations. The study aimed to derive regression equation for age estimation by investigating the relationship between chronological age and surface area of the developing mandibular 3rd molars apices. Furthermore, other predictor variables: ethnicity (Malay and Chinese), gender and status of the root development completion (open/closed apices) were also investigated in terms of fit to the age estimation model. One hundred and twenty eight training and 55 validation samples of intact mandibular 3rd molars were selected from 183 CBCT scans. The samples comprised of 93 Malays and 90 Chinese, ranging in age from 13 to 24 years. Three-dimensional image modeling and surface area analysis of the developing mandibular 3rd molars apices were performed using Mimics and 3-Matics software. Multiple linear regression analysis was used to derive age estimation model using chronological age as a dependent variable and surface area of the apices, ethnicity, gender and status of the root development completion (open/closed apices) as predictor variables. A strong inverse correlation (r = 0.95, SD = 1.144) was observed between chronological age and all the predictor variables. The results showed that 89.6% of the variation in age can be explained by the predictor variables. Mean absolute error (MAE) value of 0.8223 was observed when the derived regression equation was tested on the independent validation sample. In conclusion, three-dimensional surface area analysis of the developing mandibular 3rd molars apices can be used as a reliable method for age estimation.
  12. Safdar A, Khan MA, Shah JH, Sharif M, Saba T, Rehman A, et al.
    Microsc Res Tech, 2019 Sep;82(9):1542-1556.
    PMID: 31209970 DOI: 10.1002/jemt.23320
    Plant diseases are accountable for economic losses in an agricultural country. The manual process of plant diseases diagnosis is a key challenge from last one decade; therefore, researchers in this area introduced automated systems. In this research work, automated system is proposed for citrus fruit diseases recognition using computer vision technique. The proposed method incorporates five fundamental steps such as preprocessing, disease segmentation, feature extraction and reduction, fusion, and classification. The noise is being removed followed by a contrast stretching procedure in the very first phase. Later, watershed method is applied to excerpt the infectious regions. The shape, texture, and color features are subsequently computed from these infection regions. In the fourth step, reduced features are fused using serial-based approach followed by a final step of classification using multiclass support vector machine. For dimensionality reduction, principal component analysis is utilized, which is a statistical procedure that enforces an orthogonal transformation on a set of observations. Three different image data sets (Citrus Image Gallery, Plant Village, and self-collected) are combined in this research to achieving a classification accuracy of 95.5%. From the stats, it is quite clear that our proposed method outperforms several existing methods with greater precision and accuracy.
  13. Safpbri Johari, Muhammad Abdul Jalil, Shaifol Ifrad Ibrahim, Mohd Nazry Mohammad, Norhafiza Hassan
    MyJurnal
    Recently, the industry and academia there is significant activity in research and development towards the next generation micro and Pico cellular wireless Networks (5th generation). This paper presents, a structure design of microstrip patch antenna array operate at the central frequency of 28 GHz waveband is proposed. The patch antenna array consists of four elements with rectangular patch and uniform distribution. It has a compact size of 26.51 x 20.37 mm with operating frequency at 28 GHz. The inset feed technique is used for the matching between radiating patch and the 50Ω microstrip feedline. The proposed 2x2 antenna array successfully improve the antenna gain up to 8.393dB compare to existing CRLH TL CPW antenna with 2.99 dB, wideband antenna with 7.1 dB and 3.7 dB for broadband elliptical-shaped slot antenna. As a conclusion, the directivity of 10.13 db and efficiency is higher than 80% considered as a potential candidate for the 5G wireless networks and applications.
  14. Rahim S, Ayob MTM, Hasim MH, Abdul Rahman I, Radiman S
    Luminescence, 2019 Nov;34(7):699-706.
    PMID: 31293037 DOI: 10.1002/bio.3655
    Gd2 O2 S:Eu3+ nanophosphors have been successfully synthesized using microwave irradiation and γ-irradiation methods with polyvinyl pyrrolidone as a stabilizer. The physical and luminescence spectra were compared. The morphologies of both Gd2 O2 S:Eu3+ nanophosphors were in the hexagonal phase and mainly consisted of spherical nanostructures with diameters of ~90 nm and ~50 nm for both microwave irradiation and γ-irradiation methods. Upon 325 nm of ultraviolet (UV) light excitation, strong red emissions (626 nm) were observed for both methods; these emissions corresponded to the 5 D0 →7 F2 transition of Eu3+ ions. However, Gd2 O2 S:Eu3+ nanophosphors following microwave treatment showed better luminescence intensity than Gd2 O2 S:Eu3+ nanophosphors treated with γ-irradiation. This difference was attributed to the crystallinity phase and surface quenching effects of Gd2 O2 S:Eu3+ nanophosphors. The reaction mechanisms of Gd2 O2 S:Eu3+ nanophosphors in both methods are discussed in detail.
  15. Faheem M, Fizza G, Ashraf MW, Butt RA, Ngadi MA, Gungor VC
    Data Brief, 2021 Apr;35:106854.
    PMID: 33659599 DOI: 10.1016/j.dib.2021.106854
    Smart Grid Industry 4.0 (SGI4.0) defines a new paradigm to provide high-quality electricity at a low cost by reacting quickly and effectively to changing energy demands in the highly volatile global markets. However, in SGI4.0, the reliable and efficient gathering and transmission of the observed information from the Internet of Things (IoT)-enabled Cyber-physical systems, such as sensors located in remote places to the control center is the biggest challenge for the Industrial Multichannel Wireless Sensors Networks (IMWSNs). This is due to the harsh nature of the smart grid environment that causes high noise, signal fading, multipath effects, heat, and electromagnetic interference, which reduces the transmission quality and trigger errors in the IMWSNs. Thus, an efficient monitoring and real-time control of unexpected changes in the power generation and distribution processes is essential to guarantee the quality of service (QoS) requirements in the smart grid. In this context, this paper describes the dataset contains measurements acquired by the IMWSNs during events monitoring and control in the smart grid. This work provides an updated detail comparison of our proposed work, including channel detection, channel assignment, and packets forwarding algorithms, collectively called CARP [1] with existing G-RPL [2] and EQSHC [3] schemes in the smart grid. The experimental outcomes show that the dataset and is useful for the design, development, testing, and validation of algorithms for real-time events monitoring and control applications in the smart grid.
  16. Mohd Shaiful Ehsan Shalihin, Iskandar Firzada Osman, Muhammad Hapizie Bin Din
    MyJurnal
    Introduction: Long waiting time is a common issue complained by diabetic patients that came for an
    early morning appointment in a health clinic. Therefore, an audit was conducted among diabetic patients in
    a primary care clinic with the aim to assess the patients’ waiting time and to formulate strategies for
    improvement. Methods: This audit was conducted for four weeks using a universal sampling method in
    November 2017. All diabetic patients who attended the clinic during this period were included except those
    who required longer period such as critically ill patients or those who came for repeat medication or
    procedures. The arrival and departure time for each station was captured using the modified waiting time
    slip, which is manually filled at every station. The waiting and consultation time for registration, screening,
    laboratory investigation, diabetic educator, doctor and pharmacy were recorded. The data were entered into
    the statistical software SPSS version 17 for analysis. Results: Results showed that all patients were registered
    within 11.0 minutes (SD=2.52min). Average total waiting time to see a diabetic educator and a doctor was
    20.9 minutes (SD=15.53min) and 33.23 minutes (SD=27.85min), respectively. Average waiting time for other
    stations was less than 10 minutes. Average total time spend in the clinic for a diabetic patient was 107.58
    minutes, which is comparable to a non-diabetic patient. The identified problems were due to the poor
    tracing and filing system. Conclusion: Improvement strategies recommended include enforcing early file
    tracing prior to appointment and providing a checklist for consultation by doctors and diabetic educators.
  17. Tahir M, Upadhyay DK, Iqbal MZ, Rajan S, Iqbal MS, Albassam AA
    J Pharm Bioallied Sci, 2020 10 08;12(4):436-443.
    PMID: 33679090 DOI: 10.4103/jpbs.JPBS_263_20
    Introduction: Community pharmacist's knowledge about the uses of herbal medicines and its adverse drug reactions reporting can contribute in better therapeutic outcomes and patient safety. Objectives: To evaluate community pharmacists' knowledge about the use of herbal medicines and its adverse drug reactions reporting in Kedah state, Malaysia.

    Methods: A cross-sectional, questionnaire-based study was conducted among 103 pharmacists from 74 different community pharmacies to assess their knowledge about the use of herbal medicines and its adverse drug reaction reporting by using a pre-validate knowledge questionnaire consisting of 12 questions related to it. The pharmacists' responses were measured at a 3-point Likert scale (Poor=1, Moderate=2, and Good=3) and data was entered in SPSS version 22. The minimum and maximum possible scores for knowledge questionnaires were 12 and 36 respectively. Quantitative data was analyzed by using One Way ANOVA and Paired t-test whereas Chi-square and Fisher exact test were used for qualitative data analysis. A p-value of less than 0.05 was considered statistically significant for all the analyses.

    Results: About 92% of the pharmacist had good knowledge regarding the use of herbal medicines and its adverse drug reaction reporting with a mean knowledge score of 32.88±3.16. One-way ANOVA determined a significant difference of employment setting (p<0.043) and years of experience (<0.008) with mean knowledge scores of Pharmacists. Pharmacists' knowledge was significantly associated with their years of experience with the Chi-square test.

    Conclusion: Pharmacists exhibit good knowledge regarding the use of herbal medicines and its adverse drug reaction reporting. However, with an increasing trend of herbal medicine use and its adverse drug reaction reporting it recalls the empowerment of experienced pharmacists with training programs in this area for better clinical outcomes.

  18. Abdelnasir S, Anwar A, Kawish M, Anwar A, Shah MR, Siddiqui R, et al.
    AMB Express, 2020 Jul 17;10(1):127.
    PMID: 32681358 DOI: 10.1186/s13568-020-01061-z
    Acanthamoeba castellanii can cause granulomatous amoebic encephalitis and Acanthamoeba keratitis. Currently, no single drug has been developed to effectively treat infections caused by Acanthamoeba. Recent studies have shown that drugs conjugated with nanoparticles exhibit potent in vitro antiamoebic activity against pathogenic free-living amoebae. In this study, we have developed a nano drug delivery system based on iron oxide nanoparticles conjugated with metronidazole which were further loaded with amphotericin B to produce enhanced antiamoebic effects against Acanthamoeba castellanii. The results showed that metronidazole-nanoparticles-amphotericin B (Met-MNPs-Amp) significantly inhibited the viability of these amoebae as compared to the respective controls including drugs and nanoparticles alone. Met-MNPs-Amp exhibited IC50 at 50 μg/mL against both A. castellanii trophozoites and cysts. Furthermore, these nanoparticles did not affect the viability of rat and human cells and showed safe hemolytic activity. Hence, the results obtained in this study have potential utility in drug development against infections caused by Acanthamoeba castellanii. A combination of drugs can lead to successful prognosis against these largely neglected infections. Future studies will determine the value of conjugating molecules with diagnostic and therapeutic potential to provide theranostic approaches against these serious infections.
  19. Chaudhry MH, Ahmad A, Gulzar Q, Farid MS, Shahabi H, Al-Ansari N
    Sensors (Basel), 2021 Feb 27;21(5).
    PMID: 33673425 DOI: 10.3390/s21051649
    Unmanned Aerial Vehicle (UAV) is one of the latest technologies for high spatial resolution 3D modeling of the Earth. The objectives of this study are to assess low-cost UAV data using image radiometric transformation techniques and investigate its effects on global and local accuracy of the Digital Surface Model (DSM). This research uses UAV Light Detection and Ranging (LIDAR) data from 80 meters and UAV Drone data from 300 and 500 meters flying height. RAW UAV images acquired from 500 meters flying height are radiometrically transformed in Matrix Laboratory (MATLAB). UAV images from 300 meters flying height are processed for the generation of 3D point cloud and DSM in Pix4D Mapper. UAV LIDAR data are used for the acquisition of Ground Control Points (GCP) and accuracy assessment of UAV Image data products. Accuracy of enhanced DSM with DSM generated from 300 meters flight height were analyzed for point cloud number, density and distribution. Root Mean Square Error (RMSE) value of Z is enhanced from ±2.15 meters to 0.11 meters. For local accuracy assessment of DSM, four different types of land covers are statistically compared with UAV LIDAR resulting in compatibility of enhancement technique with UAV LIDAR accuracy.
  20. Muhammad Danial Abu Hasan, Zair Asrar Ahmad, Mohd Salman Leong, Lim, Meng Hee
    MyJurnal
    The present paper deals with the novel approach for clustering using the image feature of stabilization diagram for automated operational modal analysis in parametric model which is stochastic subspace identification (SSI)-COV. The evolution of automated operational modal analysis (OMA) is not an easy task, since traditional methods of modal analysis require a large amount of intervention by an expert user. The stabilization diagram and clustering tools are introduced to autonomously distinguish physical poles from noise (spurious) poles which can neglect any user interaction. However, the existing clustering algorithms require at least one user-defined parameter, the maximum within-cluster distance between representations of the same physical mode from different system orders and the supplementary adaptive approaches have to be employed to optimize the selection of cluster validation criteria which will lead to high demanding computational effort. The developed image clustering process is based on the input image of the stabilization diagram that has been generated and displayed separately into a certain interval frequency. and standardized image features in MATLAB was applied to extract the image features of each generated image of stabilisation diagrams. Then, the generated image feature extraction of stabilization diagrams was used to plot image clustering diagram and fixed defined threshold was set for the physical modes classification. The application of image clustering has proven to provide a reliable output results which can effectively identify physical modes in stabilization diagrams using image feature extraction even for closely spaced modes without the need of any calibration or user-defined parameter at start up and any supplementary adaptive approach for cluster validation criteria.
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