29 research outputs found
Assessing and comparing PM10 pollutant behaviour using functional data approach
This study highlights the advantage of functional data approach in assessing and comparing the PM10 pollutant behaviour as an alternative statistical approach during and between the two extreme haze years (1997 and 2005) that have been reported in Selangor, state of Malaysia. The aim of the study was to improvise the current conventional methods used in air quality assessment so that any unforeseen implicit information can be revealed and the previous research findings can be justified. An analysis based on the daily diurnal curves in place of discrete point values was performed. The analysis results provided evidences of the influence of the change in the climate (due to the El-Nino event), the different levels of different emission sources and meteorological conditions on the severity of the PM10 problem. By means of the cummulative exceedence index and the functional depth method, most of the monitoring stations for the year 2005 experienced the worst day of critical exceedences on the 10th of August, while for the year 1997 it occurred between 13th and 26th September inclusively at different dates among the stations
Study Karakteristik Pengabutan Nozzle Engine Shanghai SC11B220G2B1 Dengan Variasi Tekanan
This study aims to determine the length of the fission penetration tip and the friction angle by using variations in pressure of 100 bar, 150 bar, 200 bar, 250 bar and 300 bar.
The measurement process is done by first adjusting the pressure of the injector tester nozzle, then pressing the nozzle injector tester lever. And start recording the measurement process using a high divination camera. After obtaining the recording characteristics of the fading, then process it into the Image J software to get more accurate data.
The measurement results of the fission penetration tip length in each pressure variation have the same result which is 20 cm. The measurement results of the fog angle at a pressure of 100 bar = 15 °, 150 bar = 17 °, 200 bar = 17 °, 250 bar = 19 °, and 300 bar = 21 °
Implementasi Metode Waterfall Dalam Mengembangkan Sistem Informasi Ujian Online Dengan Fitur Proctoring
Sistem ujian online berbasis web dengan fitur pengawasan proctoring telah menjadi tren yang populer dalam lembaga pendidikan dan perguruan tinggi saat ini. Penelitian ini bertujuan untuk merancang dan mengembangkan sistem informasi ujian online yang aman dan terpercaya dengan fitur pengawasan proctoring. Sistem ini memberikan fleksibilitas waktu dan tempat bagi peserta ujian, sambil mengurangi biaya dan upaya administratif yang terkait dengan ujian konvensional. Metode pengembangan Perangkat lunak yang digunakan yaitu waterfall, dengan tahapan analisis kebutuhan, perancangan, implementasi, testing, dan perawatan. Model yang diusulkan mampu mengefisiensikan kegiatan ujian disekolah serta kecurangan dalam ujian dapat di minimalisir
Effects of concurrent TeO2 reduction and ZnO addition on elastic and structural properties of (90 − x)TeO2–10Nb2O5–(x)ZnO glass
Niobium-containing tellurite glass with starting composition of (90 − x)TeO2–10Nb2O5–(x)ZnO (x = 0–15 mol%) have been prepared by melt-quenching method and the effect of reduction of TeO2 with simultaneous increase in ZnO on elastic properties was studied. Ultrasonic longitudinal and shear velocity showed initial decrease of 3.52% and 2.37%, respectively, at x = 5 mol%. For x > 5 mol%, longitudinal velocity showed weak recovery but shear velocity showed steady recovery with ZnO and recorded 0.95% increase in value at x = 15 mol% compared to x = 0 sample. Shear and Young's moduli recorded similar drop at x = 5 mol% followed by strong recovery at x > 5 mol%, while longitudinal and Bulk modulus showed weak and no recovery, respectively, with x. Infrared (IR) absorption spectra showed increase in intensity of NbO6-assigned peak accompanied by increase in intensity of ZnO4 tetrahedra and TeO4 trigonal bipyramid (tbp) assigned peaks indicating formation of both non-bridging oxygen, NBO and bridging oxygen, BO, respectively, with addition of ZnO. The initial drop in ultrasonic velocity and related elastic moduli observed at x = 5 mol% indicates weakening of network rigidity of the glass system due to structural modification as a direct effect of TeO2 reduction and existence of NBO. However, further replacement of TeO2 by ZnO at x > 5 mol% contributed to increase in BO causing rigidity of the glass network to improve. In addition, hardness, H, was observed to increase with ZnO indicating increase in connectivity of the glass network while Poisson's ratio, σ, decreased indicating increase in cross-link density of the glass system. The combined results of ultrasonic velocity and IR absorption spectra suggest that the role of TeO2 is very critical in the ternary glass system as, although ZnO addition showed improved rigidity due to recovery of shear modulus, the weakening of longitudinal and Bulk moduli indicates ZnO is not fully effective as glass former in place of TeO2
Pengaruh beban biaya transaksi dan kualitas pelayanan mobile banking terhadap kepuasan nasabah
Penelitian ini dilatarbelakangi oleh hasil penelitian sebelumnya yang telah menjelaskan bahwa aplikasi mobile banking dalam sistem pelayanan perbankan menghasilkan implikasi yang positif terhadap kepuasan nasabah. Namun dalam beberapa kasus, kepuasan nasabah juga sangat dipengaruhi oleh tingkat kompetisi besaran beban biaya transaksi dan kualitas pelayanan yang diberikan oleh setiap lembaga keuangan dan perbankan. Oleh karena itu, penelitian ini akan difokuskan untuk menganalisis pengaruh beban biaya transaksi dan kualitas pelayanan mobile banking terhadap kepuasan nasabah PT. Bank Jabar Banten Syariah. Penelitian ini menggunakan metode deskriptif-empirik dan pendekatan kuantitatif. Sumber dan teknik pengumpulan data dilakukan melalui observasi, wawancara, dan studi kepustakaan. Teknik analisis data menggunakan analisis regresi linier berganda. Hasil penelitian ini menunjukan bahwa beban biaya transaksi dan kualitas pelayanan secara simultan berpengaruh terhadap kepuasan nasabah PT. Bank Jabar Banten Syariah. Hal ini ditunjukan dengan hasil Fhitung > Ftabel yaitu 14,514 > 3,05 dengan tingkat signifikansi 0,000 < level signifikasi . Hasil uji simultan menunjukan bahwa beban biaya transaksi dan kualitas pelayanan berpengaruh sangat signifikan terhadap kepuasan nasabah sebesar 63,1%, sedangkan sisanya sebesar 36,9% dipengaruhi oleh faktor lain yang tidak diteliti dalam penelitian ini
Preliminary Study of Poly(Tetrahydrofurfuryl Acrylate) Thin Film as a Potential Material of Ion Selective Electrodes: The Case of Nitrate Ion-Selective Electrode
A preliminary study on the use of a photocurable poly-tetrahydrofurfuryl acrylate (pTHFA) has been successfully performed as an alternative membrane for application in the Ion-Selective Electrode (ISE) sensors such as Nitrate-ISE. The pTHFA membrane was synthesized using photopolymerization technique and further optimized by varying the concentration of the photo-initiator. The pTHFA photopolymer was characterized by C-NMR, H-NMR, FTIR, and DSC. The best sensing formulation comprising pTHFA photopolymer was obtained from composition II with Tg of -17.3 °C. In the Nitrate-ISE fabrication process, initially, the tetraoctylammonium nitrate (TOAN) ionophore was optimized. The optimum TOAN concentration of 4.2 mg was then immobilized onto composition II as a sensing matrix. Results showed that the pTHFA based ISE sensor exhibited a slope near the Nernstian number with a good linear response for detecting nitrate ion concentration between 10–1 to 10–4 M (r2 = 0.9994) and limit of detection as low as 3.47 × 10–5 M. Furthermore, the selectivity behavior of pTHFA based nitrate-ISE sensor was determined in various types of interfering ions such as SO42–, H2PO4–, HPO42–, Cl– and I–. The sensor has demonstrated selectivity coefficient of -2.27 ± 0.2, -2.49 ± 0.6, -2.18 ± 0.8, -1.31 ± 0.1 and 0.41 ± 0.2, respectively. The fabricated pTHFA ISE-Nitrate sensor was further tested in the fish ponds, soils, and also rivers. The sensors have shown excellent performance and is comparable to the standard method
Computational fluid dynamics (CFD) validation and investigation the effect of piston bowl geometries performance on port fuel injection-homogeneous charge compression ignition (PFI-HCCI) engines
Homogeneous charge compression ignition (HCCI) is an advanced combustion strategy proposed to provide higher efficiency and lower emissions than conventional compression ignition. Nevertheless, the operation of HCCI engines still presents formidable challenges. Preparing homogeneous mixtures and controlling the combustion phase are crucial challenges in the context of engine performance. Piston bowl geometry significantly enhances the process by improving the flow and facilitating air-fuel mixing for combustion. On that note, this study utilised the CFD simulation methods to analyse HCCI combustion in port fuel injection (PFI) mode and evaluate the effect of piston bowl geometries on engine performance. For this purpose, the CFD simulation result for a single-cylinder, four-stroke YANMAR diesel engine was validated with experimental data. The different piston bowl geometries with the same volume, compression, and equivalence ratio were then investigated numerically. The validation result of the CFD simulation offers enough confidence to continue the study with different piston bowl geometries. The results attained from the Direct Injection (DI) engine piston bowl application demonstrate a minor change in in-cylinder pressure and heat release rate. The piston bowl design employed in a Port Fuel Injection engine application exhibited different combustion phases while demonstrating similarity in attaining in-cylinder pressure. The findings for swirl induce piston bowl design indicate an enhancement of in-cylinder pressure for the Spiral Crown geometry model, reaching 9.42 MPa. The results of the study demonstrated that the piston bowl's design affected the performance of an HCCI engine
Coordinate systems integration for development of Malaysian craniofacial database
This study presents a data registration method for craniofacial spatial data of different modalities. The data consists of three dimensional (3D) vector and raster data models. The data is stored in object relational database. The data capture devices are laser scanner, CT (computed tomography) scan and CR (close range) photogrammetry. The objective of the registration is to transform the data from various coordinate systems into a single 3-D Cartesian coordinate system. The standard error of the registration obtained from multimodal imaging devices using 3D affine transformation is in the ranged of 1-2 mm. This study is a step forward for storing the spatial craniofacial data in one reference system in databas
Amperometric biosensor based on carbon paste mixed with enzyme, lipid and cytochrome c
info:eu-repo/semantics/publishe