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Area-Based Rainfall Rate Model for Specific Attenuation in the Equatorial Region
Get PDFThe advent of new telecommunication systems with large bandwidths like 5G/6G and satellites operating at higher frequency bands such as Ku, Ka-band, and even Q/V bands, has brought to the forefront the issue of rain attenuation, particularly in equatorial and tropical regions. Many existing models developed to address these inaccuracies in the rainfall rate prediction rely on a single rain gauge measurement, which still can lead to inaccuracy when the model is generalized for a larger area. This research, therefore, is of utmost importance as it aims to develop an area-based rainfall rate model using multiple rain gauges spread across many locations in a specific area. The area of focus for this research is the Klang Valley area, a crucial economic territory that includes the capital city, Kuala Lumpur, in Malaysia. Five rain gauges distributed in Klang Valley were chosen to measure the rainfall rate. The rainfall rate model was then developed based on the data from these five rain gauges. The results indicate that each rain gauge's rainfall rate at R0.01% exceedance level varied greatly from 102 mm/hr to 138 mm/hr and exceeded Malaysia's recommended ITU-R at 100 mm/hr. The new model, presented herein, accounts for the variation of rainfall rate across a larger area, which can provide accurate modeling of specific attenuation and rain attenuation in the equatorial regions, thereby enhancing the reliability of communication systems.
ABSTRAK: Kemunculan sistem telekomunikasi jalur lebar baru seperti 5G/6G dan satelit yang beroperasi pada jalur frekuensi tinggi seperti Ku, Ka-band, dan jalur Q/V, menyebabkan penurunan ketara amplitud gelombang akibat hujan, terutamanya di kawasan khatulistiwa dan tropika. Kebanyakan model sedia ada yang dibangunkan bagi menangani ketidak tepatan ramalan kadar hujan hanya berdasarkan pengukuran dari satu tolok hujan, ini menyebabkan ketidaktepatan model itu apabila digeneralisasikan bagi kawasan lebih luas. Oleh itu, kajian ini adalah amat penting kerana ia bertujuan bagi membangunkan model kadar hujan berasaskan kawasan menggunakan beberapa tolok hujan yang tersebar di pelbagai lokasi pada satu kawasan tertentu. Kawasan tumpuan kajian ini adalah kawasan Lembah Klang, sebuah wilayah ekonomi penting yang melingkupi ibu negara, Kuala Lumpur, Malaysia. Lima tolok hujan yang tersebar di Lembah Klang dipilih bagi mengukur kadar hujan. Model kadar hujan kemudiannya dibangunkan berdasarkan data dari kelima-lima tolok hujan ini. Dapatan menunjukkan kadar hujan R0.01% bagi lima tolok hujan adalah antara 102 mm/jam hingga 138 mm/jam dan melebihi kadar cadangan ITU-R Malaysia iaitu pada 100 mm/jam. Model baru yang mengambil kira variasi kadar hujan pada suatu kawasan lebih luas menggunakan banyak tolok hujan, di mana dapat memberikan pemodelan amplitud gelombang yang lebih tepat bagi hujan di kawasan khatulistiwa, dengan itu meningkatkan kebolehpercayaan sistem komunikasi
CHARACTERISATION OF POMACEA CANALICULATA EGGS TREATED WITH PROTEASE
Get PDFPomacea canaliculata is a type of freshwater snail that has become a major pest in paddy fields, as it feeds on young paddy leaves and stems, thus, posing a serious threat to paddy production. It was named one of the world's top 100 worst invasive species, with serious consequences for the environment, human health, and the social economy. Their hatchability rate is high, which explains their global distribution worldwide. Therefore, it is vital to manage their hatchability to prevent their population from expanding further by understanding the protection that permits the eggs to survive. P. canaliculata eggs are covered with a thin layer of cuticle that is rich in protein to protect the embryo during the hatching process. The biological treatment with protease enzyme successfully hydrolysed the protein cuticle layer, lowering the percentage of hatchability. Disruption of the protein cuticle may have an impact on conductivity, water loss, hatching time, protein content, and other factors. However, documentation of the protease effect on the protein cuticle is scarce. Therefore, the goal of this study is to evaluate the protease treatment on the protein cuticle of P. canaliculata eggs physically (conductivity, water loss, and morphological analysis) and chemically (cuticle protein content, protein breakdown, and amino acid profile). Physical characterisation revealed that protease-treated eggs have higher conductivity and water loss than the control egg. Images taken with a light microscope (LM) and a scanning electron microscope (SEM) revealed changes in cuticle structure, which explained the protease-induced cuticle hydrolysis. Chemical characterisation revealed a decrease in cuticle protein content, hydrolysis of protein to a small size, and changes in amino acid composition. The physical and chemical analyses strongly suggested that protease can damage the cuticle protein, thus, preventing the eggs from hatching.
ABSTRAK: Pomacea canaliculata adalah sejenis siput air tawar yang telah menjadi perosak utama di sawah padi, kerana ia memakan daun dan batang padi yang muda, sekaligus menimbulkan ancaman serius kepada pengeluaran padi. Ia disenaraikan antara 100 spesis invasif utama dunia dengan kesan serius pada alam sekitar, kesihatan manusia dan sosio-ekonomi. Kadar penetasannya adalah tinggi, meningkatkan penyebaran mereka secara global di seluruh dunia. Oleh itu, adalah sangat penting untuk mengawal populasi ini daripada terus berkembang dengan memahami perlindungan yang membenarkan telur untuk hidup. Telur P.canaliculata dilapisi dengan lapisan kutikel nipis yang kaya dengan protein bagi memberi perlindungan untuk embrio semasa proses penetasan. Rawatan biologi dengan enzim protease telah berjaya menghidrolisis lapisan kutikel protein, sekaligus mengurangkan peratusan penetasan. Gangguan terhadap lapisan kutikel protein mungkin memberi kesan pada konduktiviti, kehilangan air, tempoh penetasan, kandungan protein dan faktor lain. Walau bagaimanapun, kesan protease ke atas kutikel protein adalah kurang. Oleh itu, objektif kajian ini adalah mengkaji rawatan protease ke atas kutikel protein telur P. canaliculata secara fizikal (konduktiviti, kehilangan air, dan analisis imej kutikel) dan secara kimia (kandungan protein kutikel, pecahan protein dan profil asid amino). Ciri fizikal menunjukkan telur yang dirawat protease mempunyai konduksi dan kehilangan air tinggi berbanding telur kawalan. Imej yang diambil dengan mikroskop cahaya (LM) dan mikroskop pengimbas elektron (SEM) mendedahkan perubahan dalam struktur kutikel, yang menjelaskan hidrolisis kutikel yang disebabkan oleh protease. Ciri kimia menunjukkan penurunan kandungan protein kutikel, saiz kecil pada hidrolisis protein, dan perubahan pada kandungan asid amino. Analisis fizikal dan kimia mencadangkan bahawa protease merosakkan protein kutikel, oleh itu menghalang telur daripada menetas
PHOTOVOLTAIC MODULE TEMPERATURE ESTIMATION MODEL FOR THE ONE-TIME-POINT DAILY ESTIMATION METHOD
Get PDFBased on the hourly solar radiation and ambient temperature, the hourly power estimation work is carried out using the conventional photovoltaic output power (PVOP) estimation model which is used in conjunction with the conventional photovoltaic module temperature (PVMT) estimation model. These hourly data must be processed further before they can be applied to the daily power estimation work. This estimation work is carried out using conventional estimation methods, which are the multiple estimation processes that are complex, time-consuming, and error prone. Therefore, to avoid these shortcomings, one estimation process is designed and used for daily power estimation work. However, this process produces an incorrect daily output power value due to an invalid module temperature value. Thus, a new PVMT estimation model is developed to solve the problem of the invalid value based on a simple linear regression analysis. The performance of the new model has been validated, giving a Normalized Root Mean Squared Error (NRMSE) value of 0.0215 and a Coefficient of Determination (R2) value of 0.9862. The correct daily output power value is produced with a valid module temperature value, giving a NRMSE value of 0.0034 and a R2 value of 0.9999. These results demonstrate the new model's applicability and makes the one estimation process accurate, easy, user-friendly, instantaneous, and direct in daily power estimation work.
ABSTRAK: Berdasarkan sinaran matahari dan suhu persekitaran per jam, kerja-kerja anggaran kuasa setiap jam dijalankan menggunakan model anggaran kuasa dari dapatan fotovolta konvensional (PVOP) yang digunakan bersempena dengan model anggaran suhu modul fotovolta konvensional (PVMT). Data per jam ini perlu diproses dengan lebih lanjut sebelum ia boleh digunakan pada kerja anggaran kuasa harian. Kerja-kerja penganggaran ini dijalankan menggunakan kaedah penganggaran konvensional, iaitu proses penganggaran berganda yang kompleks, memakan masa dan mudah ralat. Oleh itu, bagi mengelakkan kekurangan ini, satu proses anggaran direka bentuk dan diguna bagi kerja anggaran kuasa harian. Namun, proses ini menghasilkan nilai dapatan kuasa harian yang salah disebabkan oleh nilai suhu modul tidak sah. Oleh itu, model anggaran PVMT baharu telah dibina bagi menyelesaikan masalah nilai tidak sah berdasarkan analisis mudah regresi linear. Prestasi model baharu telah disahkan, memberi nilai Ralat Punca Min Kuasa Dua Ternormal (NRMSE) sebanyak 0.0215 dan nilai Pekali Penentuan (R2) sebanyak 0.9862. Nilai dapatan kuasa harian yang betul dihasilkan dengan nilai suhu modul yang sah, iaitu nilai NRMSE 0.0034 dan R2 0.9999. Dapatan ini menunjukkan bahawa kebolehgunaan model baharu menjadikan proses anggaran lebih tepat, mudah, mesra pengguna, serta-merta dan terus dalam kerja anggaran kuasa harian
Evaluation and Kinetics of Tofu Wastewater Bioreactor with Addition of Water Hyacinth
Get PDFTofu wastewater is a nitrogen-rich wastewater type with a high concentration of organic contents. To enhance the digestion rate of tofu wastewater in an anaerobic bioreactor, water hyacinth was tested as an additional substrate. Water hyacinth is a dangerous weed with a high carbon-nitrogen ratio (C/N) of about 30-35. Substrate combination was intentionally used in this study to raise the C/N of wastewater. This study aims to evaluate the digestion rate of a bioreactor qualitatively based on experimental data to determine the biokinetic constants of the anaerobic bioreactor quantitatively based on microbial growth data, substrate degradation, and methane (CH4) production. MATLAB was used as software to run mathematical modeling. The anaerobic bioreactor was designed and equipped with a circulation pump to maintain the homogeneity of the substrate and was completed with a biogas collector. Seeding and acclimatization were carried out before the main experiment started. Using a combination substrate of tofu wastewater and water hyacinth with a 5:3 volume ratio, the bioreactor was run at 20 days of hydraulic retention time (HRT) at room temperature. The bioreactor was able to remove 92.8% of chemical oxygen demand (COD) concentration and produced biogas with the highest CH4 concentration of 56.9%. The obtained kinetic constants indicate that, in comparison with similar studies of anaerobic digestion of the low C/N wastewater, the addition of water hyacinth resulted in better performance of the bioreactor with the correlation of microbial growth rate (?m), substrate degradation (YX/CCOD) and CH4 production (YCCH4/X) with the consecutive values of 0.65/day, 0.64 mg cells/mg COD, and 0.62 mg CH4/mg cells. An appropriate ratio of water hyacinth as the high carbon source and nitrogen-rich tofu wastewater is recommended to obtain the optimum ratio of carbon to nitrogen and result in a higher percentage of methane formation.
ABSTRAK: Air sisa tauhu ialah air sisa yang kaya dengan nitrogen dengan kepekatan kandungan organik yang tinggi. Bagi meningkatkan kadar penghadaman air sisa tauhu dalam bioreaktor anaerobik, keladi bunting diuji sebagai substrat tambahan. Keladi bunting merupakan rumpai berbahaya dengan nisbah karbon nitrogen (C/N) yang tinggi iaitu kira-kira 30-35. Gabungan substrat sengaja digunakan dalam kajian ini bagi menaikkan C/N air sisa. Kajian ini bertujuan bagi menilai kadar pencernaan bioreaktor secara kualitatif berdasarkan data eksperimen dan menentukan pemalar biokinetik bioreaktor anaerobik secara kuantitatif berdasarkan data pertumbuhan mikrob, degradasi substrat, dan pengeluaran metana (CH4). MATLAB digunakan sebagai perisian pemodelan matematik. Bioreaktor anaerobik direka bentuk dan dilengkapi dengan pam edaran bagi mengekalkan kehomogenan substrat dan dilengkapkan dengan pengumpul biogas. Penyemaian dan penyesuaiikliman telah dijalankan sebelum eksperimen utama bermula. Substrat gabungan air sisa tauhu dan keladi bunting digunakan dengan nisbah isipadu 5:3. Bioreaktor dijalankan selama 20 hari iaitu masa pengekalan hidraulik (HRT) pada suhu bilik. Bioreaktor tersebut mampu mengasingkan 92.8% kepekatan permintaan oksigen kimia (COD) dan menghasilkan biogas dengan kepekatan CH4 tertinggi sebanyak 56.9%. Pemalar kinetik yang diperoleh menunjukkan bahawa, berbanding dengan kajian serupa tentang pencernaan anaerobik air sisa C/N rendah, penambahan keladi bunting menghasilkan prestasi bioreaktor yang lebih baik dengan korelasi kadar pertumbuhan mikrob (?m), degradasi substrat (YX/CCOD) dan penghasilan CH4 (YCCH4/X) dengan nilai masing-masing 0.65/hari, 0.64 mg sel/mg COD, dan 0.62 mg CH4/mg sel. Nisbah keladi bunting yang sesuai sebagai sumber karbon tinggi dan air sisa tauhu yang kaya dengan nitrogen disyorkan agar mendapatkan nisbah optimum karbon kepada nitrogen dan ini menghasilkan peratusan pembentukan metana yang lebih tinggi
MIXING SEQUENCE EFFECT OF CEMENT COMPOSITES WITH CARBON FIBRES
Get PDFCarbon fibres are widely recognised as reinforcement materials that effectively control cracks in concrete structures. Nonetheless, these fibres do not disperse uniformly inside the cement matrix, disrupting the mixture homogeneity. To address this concern, this study investigated two distinct mixing sequences of cement composites with carbon fibres. Two mixing sequences were investigated including the addition of fibres after cement (AC-CF) and the addition of fibres before cement (BC-CF). The surface topography of carbon fibres and the engineering properties of the cement paste were also examined. Consequently, carbon fibres in cement composite produced lower flowability due to the surface roughness. The AC-CF specimen demonstrated the highest hardened density at 28 days with 2679.22 kg/m3 followed by BC-CF and the control specimen with 2386.08 kg/m3 and 2278.36 kg/3, respectively. The AC-CF specimen also had the highest compressive strength at 28 days with 69.91 MPa, followed by BC-CF and the control specimen with 65.92 MPa and 63.20 MPa, respectively. Further, the flexural strength of the AC-CF specimen exhibited the highest strength with 10.86 MPa, followed by BC-CF and the control specimen with 9.35 MPa and 9.17, respectively. The fibre dispersion in AC-CF was also superior to BC-CF. Therefore, it can be concluded that the best mixing sequence is the addition of fibre after cement (AC-CF) because it had better fibre dispersion and engineering properties compared to the addition of fibre before cement (BC-CF).
ABSTRAK: Gentian karbon lebih dikenali sebagai bahan bantuan yang berkesan dalam mengawal keretakan pada struktur konkrit. Walau bagaimanapun, gentian ini tidak tersebar secara seragam di dalam matrik simen dan akan mengganggu kehomogenan campuran. Bagi mengatasi masalah ini, kajian ini mengkaji tentang dua susunan campuran berbeza simen komposit dengan gentian karbon. Dua susunan campuran ini adalah melalui penambahan gentian selepas simen (AC-CF) dan penambahan gentian sebelum simen (BC-CF). Permukaan topografi gentian karbon dan sifat kejuruteraan pes simen turut diperiksa. Kajian mendapati bahawa gentian karbon dalam komposit simen mengurangkan kebolehaliran pes simen disebabkan oleh kekasaran pada permukaan gentian. Spesimen AC-CF menunjukkan ketumpatan pengerasan tertinggi pada hari ke-28 dengan 2679.22 kg/m3 diikuti spesimen BC-CF dan spesimen kawalan sebanyak 2386.08 kg/m3 dan 2278.36 kg/m3, masing-masing. Spesimen AC-CF juga mempunyai kekuatan mampatan tertinggi pada hari ke-28 dengan 69.91 MPa, diikuti oleh spesimen BC-CF dan spesimen kawalan sebanyak 65.92 MPa dan 63.20 MPa, masing-masing. Seterusnya, kekuatan lenturan spesimen AC-CF menunjukkan kekuatan tertinggi dengan 10.86 MPa, diikuti spesimen BC-CF and spesimen kawalan dengan 9.35 MPa dan 9.17 MPa, masing-masing. Penyebaran gentian dalam AC-CF juga lebih baik daripada BC-CF. Oleh itu, kajian ini merumuskan bahawa susunan campuran terbaik adalah dengan penambahan gentian selepas simen (AC-CF) kerana ia mempunyai kekuatan lenturan gentian terbaik dan sifat kejuruteraan berbanding penambahan gentian sebelum simen (BC-CF)
Exploring the Efficacy of Piezoelectric-Based Sensory Systems for Heart Rate Monitoring in Differentiating Stress vs. Relax Conditions
Get PDFStress has diverse effects on human physiological reactions, and one such effect is on heart rate (HR). The established methods to acquire HR is by electrocardiogram (ECG) and photoplethysmogram (PPG). ECG electrodes need to be placed on the chest, which can cause inconvenience and is not practical in daily life, while PPG signals are known to contain more noise than ECG. Thus, this work aims to investigate the efficacy of a piezoelectric-based sensory system in measuring HR and using the signal to differentiate stressed and relaxed conditions by means of statistical analysis. Two activities were conducted to achieve the goal. The first experiment involved collecting and analysing piezoelectric signals to measure the pulse rate (bpm) and compare this with the HR from PPG. For the second experiment, the piezoelectric-based HR was calculated from 20 subjects (male and female, age ranging between 20 and 25) in relaxed and stressed conditions. The stress condition was triggered using two stressors: the Stroop Colour Word Test and the Digit Span Test. Statistical analyses reveal a strong positive correlation between piezoelectric-based heart rate (HR) and oximeter readings (r(12) = 0.993, p < 0.001), despite the fact that the values are not precisely identical. In addition, the findings also indicate that there are significant effects by the mental states (stressed and relaxed) on the piezoelectric-based HR readings (p<0.05). Employing a within-subject design condition, the results further illustrated that piezoelectric readings are elevated during stressed conditions (Mean±SD = 72.395±0.097) and diminished during relaxed conditions (Mean±SD = 71.615±0.126). Therefore, the suggested piezoelectric-based sensory system has been validated as an effective means of categorizing stress and relaxation based on heart rate signals.
ABSTRAK: Tekanan mempunyai pelbagai kesan terhadap reaksi fisiologi manusia dan satu daripadanya adalah kadar denyut jantung (HR). Kaedah biasa bagi mengetahui HR adalah melalui elektrokardiogram (ECG) dan fotofetismogram (PPG). Elektrod ECG perlu dipasang pada dada di mana boleh menyebabkan ketidakselesaan dan tidak praktikal dalam kehidupan seharian, manakala isyarat PPG diketahui mengandungi lebih banyak bunyi berbanding ECG. Oleh itu, kajian ini bertujuan mengkaji kecekapan ystem deria berdasarkan piezoeletrik bagi mengukur HR dan menggunakan isyarat ini bagi membezakan keadaan tertekan atau tenang melalui cara analisis ystemic. Bagi mencapai tujuan ini, dua aktiviti dijalankan. Pertama eksperimen melibatkan pengumpulan dan analisis isyarat piezoeletrik bagi mengukur kadar nadi (bpm) dan membandingkan HR daripada PPG. Eksperimen kedua, HR berdasarkan piezoelektrik dikira dari 20 subjek (lelaki dan ystemic, berumur antara 20 dan 25) dalam keadaan tenang dan tertekan. Keadaan tertekan dibuat melalui dua ystemi: Ujian Stroop Patah Warna dan Ujian Rentang Digit. Analisis ystemic mendedahkan hubungkait yang kuat antara kadar denyut jantung (HR) berdasarkan piezoeletrik dan bacaan oksimeter (r(12) = 0.993, p < 0.001), walaupun bacaan tidak benar-benar serupa. Tambahan, penemuan ini menunjukkan terdapat kesan penting terhadap tahap mental (tertekan dan tenang) pada bacaan denyut jantung (HR) berdasarkan piezoeletrik (p<0.05). Dengan mengaplikasi keadaan reka bentuk subjek, dapatan menunjukkan bacaan piezoeletrik meningkat ystem keadaan tertekan (Mean±SD = 72.395±0.097) dan kurang ystem keadaan tenang (Mean±SD = 71.615±0.126). Oleh itu, ystem deria berdasarkan piezoeletrik telah diuji berkesan dalam mengkategori keadaan tertekan dan tenang berdasarkan isyarat denyut jantung
Continuous Flow Bead-Milling Impact on Sulfur Curing for Advanced Elastomeric Rubber Composites
Get PDFAs an eco-friendly and technically feasible method for physical modification of materials, bead-milling has been extensively used in many industrial applications ranging from chemicals, nanomaterials, foods, and pharmaceuticals with impacts on particle size, surface morphology, stability, and overall products’ performance. Apparently, there have been limited studies conducted on sulfur curative dispersion using this technology, necessitating a thorough investigation of its performance. The objectives of the present study were to explore the influence of the bead-milling process parameters, particularly rotational speed and flow rate, on the sulfur curative dispersion characteristics and to analyze its behavior within the rubber elastomer matrix. Taguchi’s L9 orthogonal array experimental design was employed to identify the optimal rotational speed and flow rate of a 60-L bead-milling machine on the sulfur curative dispersion. The stability and morphology of the resulting sulfur curative dispersion were characterized, along with its mechanical properties in rubber elastomers. It was found that higher rotational speed (800 rpm) and lower flow rate (350 L/h) of the bead-milling process resulted in smaller sulfur particle sizes, leading to improved tensile strength of the rubber elastomer. This research may provide valuable insights to determine the ideal bead-milling process for sulfur curative, enhancing the mechanical properties and overall performance of elastomeric rubber composites as well as across various fields.
ABSTRAK: Sebagai sebahagian kaedah mesra alam dan secara teknikal dapat mengubah suai bentuk fizikal bahan, mesin pengisaran manik telah digunakan secara meluas dalam kebanyakan aplikasi industri termasuk kimia, nanomaterial, makanan, dan farmaseutikal dengan kesan pada saiz zarah, morfologi permukaan, kestabilan, dan prestasi keseluruhan produk. Namun, terdapat kurang kajian terhadap taburan kuratif sulfur menggunakan teknologi ini, menyebabkan penyelidikan menyeluruh diperlukan bagi menilai prestasinya. Objektif kajian ini adalah bagi mengkaji pengaruh parameter proses pengisaran manik, terutamanya pada kelajuan putaran dan kadar aliran, iaitu terhadap ciri-ciri taburan kuratif sulfur dan mengkaji tindak balasnya pada matriks elastomer getah. Reka bentuk eksperimen Taguchi L9 bersusunan ortogonal telah digunakan bagi mengenal pasti kelajuan putaran dan kadar aliran optimal mesin pengisaran manik 60 liter terhadap taburan kuratif sulfur. Kestabilan dan morfologi taburan kuratif sulfur yang terhasil telah dicirikan, bersama sifat mekanikal dalam elastomer getah. Dapatan mendapati bahawa proses pengisaran manik pada kelajuan putaran lebih tinggi (800 rpm) dan kadar aliran lebih rendah (350 L/j) menyebabkan saiz zarah sulfur lebih kecil, membawa kepada peningkatan kekuatan regangan elastomer getah. Kajian ini mungkin memberikan pengetahuan penting bagi menentukan proses pengisaran manik yang ideal untuk kuratif sulfur, meningkatkan sifat mekanikal dan prestasi keseluruhan komposit getah elastomerik serta pelbagai bidang lain
Geometric Quality Analysis of Terrestrial Laser Scanning Data for Industrial Usage
Get PDFTerrestrial laser scanning is a potential emerging technology increasingly used in several applications, including reverse engineering, digital reconstruction, deformation monitoring, forensic crime scene preservation, and construction (AEC) applications. The data tolerance accepted in these applications ranges from tens of millimeters (e.g., historical monument digitization) to tens of micrometers (e.g., industrial high-precision manufacturing and assembling). Instrument mechanism, atmospheric conditions, object surface characteristics, and scan geometry are the four main factors that affect the laser point clouds produced by the Time of Flight (TOF) 3D laser scanner. Consequently, research groups worldwide have put a significant effort into modeling the sources of TOF-TLS errors and design-specific performance evaluation methodologies. This paper investigated the influence of scanning geometry parameterized by incidence angle and the range on the quality of TOF-TLS data in industrial sites. The quality of an indoor sample dataset of an industrial case study was studied and assessed. The results showed that the incidence angle and range parameters substantially impacted the quality of the TOF-TLS data. The suggested methodology can accurately correct the laser data to eliminate the incidence angle and range effects. A revised and optimized point cloud dataset was reconstructed by utilizing these features in conjunction with the approximated quality of the individual points. Furthermore, when assessing the quality of individual point clouds, the accuracy validation obtained through the RMSE value was 3 mm based on ground-truth reference points. On the other hand, the standard deviation values computed through the Multi-Scale Model-to-model cloud (M3C2) analysis were revealed to reach 1mm, which shows better performance results than the Cloud-to-Cloud (C2C) and Cloud-to-Model (C2M) comparison analysis. However, the proposed method may result in the elimination of several significant laser points. These points of high incidence angle values are not eliminated in every instance. The effect of scanning geometry, represented by the angle of incidence with the normalized intensity of the scanning points, should be studied intensively in future studies.
ABSTRAK: Terestrial pengimbas laser adalah teknologi yang berpotensi besar dalam pelbagai aplikasi, termasuk kejuruteraan balikan, rekonstruksi digital, pengawasan perubahan bentuk, pemeliharaan tempat kejadian jenayah forensik, dan aplikasi konstruksi (AEC). Penerimaan data toleransi dalam aplikasi ini adalah dalam julat lingkungan beberapa milimeter (cth: digitalisasi monumen sejarah) sehingga beberapa mikrometer (cth: industri pembuatan berkejituan tinggi dan pemasangan). Mekanisme alatan, keadaan atmosfera, ciri-ciri permukaan objek, dan geometri pengimbas adalah empat faktor utama yang memberi kesan terhadap gumpalan asap titik laser terhasil daripada masa terbang (TOF) 3D pengimbas laser. Oleh itu, kumpulan pengkaji sedunia telah berusaha bersungguh-sungguh dalam pemodelan sumber ralat TOF-TLS dan mereka kaedah penilaian prestasi reka bentuk tertentu. Kajian ini dipengaruhi oleh geometri pengimbas berparameter sudut tuju dan julat kualiti data TOF-TLS dalam kawasan industri. Kualiti sampel set data dalam bangunan menggunakan kajian pembelajaran industri telah diteliti dan dinilai. Dapatan kajian menunjukkan sudut tuju dan julat parameter sangat mempengaruhi kualiti data TOF-TLS. Kaedah yang dicadangkan ini dapat memperbetulkan arah secara tepat iaitu kesan pengurangan sudut tuju dan julat. Set data rawak titik yang diubah dan dioptimumkan telah dibina semula dengan menggunakan ciri-ciri ini bersempena kualiti anggaran titik-titik individu. Tambahan, apabila menaksir kualiti titik rawak individu, pengesahan ketepatan yang diperoleh melalui nilai RMSE dijumpai sebanyak 3 mm berdasarkan titik-titik panduan kesahihan bumi. Di samping itu, nilai sisihan piawai yang dikira melalui analisis Model-ke-model Skala-Pelbagai Rawak (M3C2) didapati mencapai 1 mm, di mana menunjukkan dapatan prestasi lebih baik berbanding analisis Rawak-ke-rawak (C2C) dan Rawak-ke-Model (C2M) secara bandingan. Walau bagaimanapun, kaedah yang dicadangkan ini mungkin menyebabkan penyisihan beberapa titik laser penting. Titik-titik ini yang mempunyai nilai sudut tuju yang tinggi adalah tidak disisihkan pada setiap masa. Kesan pengimbas geometri, merupakan sudut tuju dengan keamatan ternormal titik-titik pengimbas, perlu dikaji dengan lebih lanjut pada masa depan
Rhodopseudomonas Palustris Collagen-Like Recombinant Protein Purification Using an Aqueous Two-Phase System
Get PDFThe potential use of recombinant collagen-like protein (recCLP) extracted from bacteria as disease-free collagen has been studied over the past decade. However, the complexity of the downstream processing generates high demand for an efficient and low-cost purification method. Aqueous two-phase system (ATPS) was adopted as a new approach to the recovery of biomolecules due to its simple, benign, and straightforward process. This study aimed to purify recombinant collagen-like protein from Rhodopseudomonas palustris using ATPS formed by a polymer/salt system. Recombinant collagen-like protein from R. palustris was partitioned in ATPS composed of polyethylene glycol (PEG) and potassium phosphate and several factors that influence the protein partitioning such as volume ratio, system pH, the concentration of polymer and salt were studied. Then, optimization of the selected ATPS conditions (PEG and salt concentration) were performed using response surface methodology (RSM). Results showed that the optimum conditions were found in ATPS with 24.80% (w/w) PEG 2000 and 29.23% (w/w) potassium phosphate with recCLP concentration of 3.23 ± 0.12 mg/mL with purification factor 7.48 ± 0.3. In comparison with the affinity chromatography method, ATPS was found to be low-cost, and time-saving with a higher protein recovery. Hence, this study demonstrated the potential application of ATPS in the recovery of recombinant CLPs for large-scale downstream processing.
ABSTRAK: Potensi penggunaan protein seperti kolagen rekombinan (recCLP) yang diekstrak daripada bakteria sebagai kolagen bebas penyakit telah dikaji sejak sedekad yang lalu. Walau bagaimanapun, kerumitan pemprosesan hiliran menjana permintaan yang tinggi untuk kaedah penulenan yang cekap dan berpatutan. Sistem akueus dua fasa (ATPS) telah diterima pakai sebagai pendekatan baharu dalam pemulihan biomolekul kerana prosesnya yang mudah. Tujuan utama kajian ini adalah untuk menyaring protein seperti kolagen rekombinan daripada Rhodopseudomonas palustris menggunakan ATPS yang dibentuk oleh sistem polimer/garam. Protein seperti kolagen rekombinan daripada R. palustris telah dibahagikan dalam ATPS yang terdiri daripada polietilena glikol (PEG) dan kalium fosfat dan beberapa faktor yang mempengaruhi pembahagian protein seperti nisbah isipadu, pH sistem, kepekatan polimer dan garam telah dikaji. Kemudian, keadaan ATPS terpilih (PEG dan kepekatan garam) telah dioptimumkan menggunakan metodologi permukaan tindak balas (RSM). Keputusan menunjukkan bahawa keadaan optimum dalam ATPS adalah 24.80% (b/b) PEG 2000 dan 29.23 % (b/w) kalium fosfat dengan kepekatan recCLP 3.23 ± 0.12 mg/mL dengan faktor penulenan 7.48 ± 0.3. Berbanding dengan kaedah kromatografi afiniti, ATPS didapati menjimatkan kos dan masa dengan pemulihan protein yang lebih tinggi. Oleh itu, kajian ini menunjukkan potensi aplikasi ATPS dalam pemulihan CLP rekombinan untuk pemprosesan hiliran berskala besar
PARAMETRIC OPTIMIZATION OF OIL PALM MESOCARP FIBER VALORIZATION WITH HYBRID OZONATION-ULTRASONIC PRETREATMENT METHOD
Get PDFOil palm mesocarp fiber is a promising lignocellulosic biomass as a raw material for valorizing biomass into more valuable products such as second-generation biofuels, biocomposites, or bioenergy. However, the lignin composition present in lignocellulosic biomass provides resistance to the valorization process and protects the cellulose composition, thereby limiting the conversion of cellulose into more valuable products. The hybrid ozonation-ultrasonic method as a lignin-degrading method is starting to be considered an effective method. Additionally, a Box-Behnken Design (BBD) was employed to investigate each independent variable's effect on pretreatment process conditions using the response surface methodology (RSM), namely reaction time (30-90) min, reaction temperature (20 -40) oC and ozone flow rate (1-3) L/min to the response of the percentage of lignin degradation (%). The optimum condition of the pretreatment process is determined using the desirability function graph. The results showed that reaction time, reaction temperature, and ozone flow rate had a significant effect on lignin degradation (p <0.05). The optimum conditions obtained the highest percentage of lignin degradation, namely 92.08% at a reaction temperature of 30 oC with an ozone flow rate of 2 L/min for 60 minutes reaction time. The decrease in lignin absorption peaks at 1638 cm-1 and 1427 cm-1 was supported by the results of the analysis of increased crystallinity in the sample after the pretreatment of lignin degradation to 80.20% and was validated by changes in the morphology of the mesocarp fiber after the pretreatment process indicating that the lignin compound had been successfully degraded from cellulose products of mesocarp fibers.
ABSTRAK: Sabut gentian kelapa sawit berpotensi sebagai bahan mentah biojisim lignoselulosa bagi menambah nilai produk biojisim seperti bahan bio api generasi kedua, biokomposit atau biotenaga. Walau bagaimanapun, komposisi lignin yang wujud dalam biojisim lignoselulosa menentang proses tambah nilai dan melindungi komposisi selulosa, dengan itu mengehadkan penukaran selulosa kepada produk yang lebih berharga. Kaedah hibrid ozonasi-ultrasonik sebagai kaedah merendahkan lignin, mula mendapat perhatian sebagai kaedah berkesan. Selain itu, Reka Bentuk Kotak-Behnken (BBD) telah digunakan bagi menyiasat setiap kesan pembolehubah bebas pada keadaan proses prarawatan menggunakan kaedah permukaan tindak balas (RSM), iaitu masa tindak balas (30-90) min, suhu tindak balas (20 -40) oC dan kadar aliran ozon (1-3) L/min terhadap tindak balas pada peratusan degradasi lignin (%). Keadaan optimum bagi proses prarawatan ditentukan menggunakan graf fungsi keboleh inginan. Dapatan kajian menunjukkan bahawa masa tindak balas, suhu tindak balas, dan kadar aliran ozon mempunyai kesan yang signifikan terhadap degradasi lignin (p<0.05). Keadaan optimum peratusan degradasi lignin tertinggi adalah pada 92.08% pada suhu tindak balas 30 oC dengan kadar aliran ozon 2 L/min selama 60 minit masa tindak balas. Penurunan puncak penyerapan lignin pada 1638 cm-1 dan 1427 cm-1 disokong oleh keputusan analisis peningkatan kehabluran sampel selepas prarawatan degradasi lignin sebanyak 80.20% dan telah disahkan oleh perubahan morfologi sabut gentian selepas proses prarawatan menunjukkan bahawa sebatian lignin telah berjaya didegradasi daripada produk selulosa sabut gentian