639 research outputs found
Kesan penggunaan koswer multimedia animasi visual terhadap pencapaian pelajar dalam mata pelajaran matematik
Ramai pelajar yang bermasalah dalam topik Pelan dan Dongakan. Ini kerana pelajar sukar untuk membayangkan objek yang tersembunyi melalui proses pengajaran dan pembelajaran (P&P) secara konvensional. Penyelidik telah membangunkan satu koswer multimedia animasi visual dalam topik Pelan dan Dongakan dengan menerapkan kesemua elemen-elemen yang dapat membantu meningkatkan kemahiran visual iaitu elemen animasi, video, audio, grafik dan teks. Seterusnya, kajian kuasi eksperimental ini turut dijalankan bertujuan untuk mengetahui kesan penggunaan koswer multimedia animasi visual terhadap pencapaian pelajar bagi mata pelajaran Matematik di sekolah menengah. Ujian Pra dan Ujian Pos digunakan untuk melihat perbezaan pencapaian yang signifikan selepas menggunakan koswer multimedia animasi visual yang menggunakan teori Kognitif Visual Wiley. Responden yang terlibat dalam kajian ini ialah seramai 40 orang pelajar Tingkatan Lima yang dibahagikan kepada dua kumpulan iaitu kumpulan rawatan dan kumpulan kawalan yang dipilih daripada sebuah sekolah di daerah Batu Pahat, Johor. Hasil analisis menunjukkan peningkatan skor min markah bagi pelajar kumpulan rawatan. Hasil analisis ujian-t (paired-sample-t-test) membuktikan bahawa wujudnya perbezaan skor min markah yang signifikan di antara markah ujian pra dan markah ujian pos bagi kumpulan rawatan. Oleh itu, terdapat perbezaan yang signifikan di antara skor min markah ujian pra dan ujian pos bagi pelajar kumpulan rawatan selepas menggunakan koswer multimedia animasi visual. Manakala instrumen soal selidik yang digunakan untuk melihat tahap penerimaan pelajar selepas menggunakan koswer multimedia animasi visual berdasarkan tiga aspek iaitu aspek isi kandungan, aspek interaksi dan aspek persembahan telah memeperolehi skor min yang tinggi bagi ketiga-tiga aspek tersebut. Dapatan kajian ini menggambarkan penggunaan koswer multimedia animasi visual dapat membantu meningkatkan pencapaian Matematik di dalam bilik darjah terutama yang tidak melibatkan pengiraan
The effects of pressure dependent constitutive model to simulate concrete structures failure under impact loads
The main objective of this paper is to explore the effect of confining pressure in the
compression and tension zone by simulating the behaviour of reinforced concrete/mortar
structures subjected to the impact load. The analysis comprises the numerical simulation of the
influences of high mass low speed impact weight dropping on concrete structures, where the
analyses are incorporated with meshless method namely as Smoothed Particle Hydrodynamics
(SPH) method. The derivation of the plastic stiffness matrix of Drucker-Prager (DP) that
extended from Von-Mises (VM) yield criteria to simulate the concrete behaviour were presented
in this paper. In which, the displacements for concrete/mortar structures are assumed to be
infinitesimal. Furthermore, the influence of the different material model of DP and VM that used
numerically for concrete and mortar structures are also discussed. Validation upon existing
experimental test results is carried out to investigate the effect of confining pressure, it is found
that VM criterion causes unreal impact failure (flexural cracking) of concrete structures
Pembangunan kemahiran penyelesaian masalah berlandaskan projek origami
Kemahiran penyelesaian masalah merupakan salah satu kaedah pengajaran yang
digunakan di dalam kelas. Ia merupakan satu proses pengajaran dan pembelajaran
yang berasaskan pengalaman dan memerlukan pelajar berfikir secara aktif. Tujuan
kajian ini dilakukan untuk mendapatkan persepsi pelajar terhadap kemahiran
menyelesaikan masalah tugasan folio dengan berlandaskan seni lipatan kertas. Ini
bagi membantu pelajar meningkatkan elemen kemahiran penyelesaian masalah
seperti mengenalpasti masalah, merancang dan melaksanakan strategi serta dapat
menyelesaikan apa jua sebarang masalah.
Kajian ini bersifat kuantitatif dengan reka bentuk eks pos fakto yang
menggunakan instrumen soal selidik secara tinjauan awal dan tinjauan akhir
seterusnya dianalisis menggunakan SPSS versi 21. Setiap keputusan dapatan
ditunjukkan dalam bentuk min, peratus dan ujian T. Sampel kajian adalah terdiri 30
orang pelajar tahun 2 semester 3 jurusan Pemesinan Industri. Dapatan keseluruhan
min sebelum aktiviti bengkel ialah 3.43 manakala selepas aktiviti bengkel min ialah
4.03. Keputusan hasil kajian ini mendapati kemahiran penyelesaian masalah selepas
menjalani aktiviti origami, berada pada tahap yang tinggi. Oleh yang demikian,
cadangan penyelidik untuk mengemukakan kemahiran penyelesaian masalah
berlandaskan kaedah origami di terima baik dan bagi membantu pihak tertentu
terutamanya Pihak Kolej Vokasional Melaka Tengah dalam menyelesaikan masalah
tugasan folio di kalangan pelaja
Axial Compression Behaviour of Full-Scale Prefabricated Wood-Wool Wall Panel
This study aims to investigate an axial compression behaviour of prefabricated wall constructed using wood-wool cement composite panel (WWCP). A total of three full scale wall specimens were fabricated at the laboratory with dimension of 2400 mm width, 2400 mm height and 147 mm thickness. The new fabrication technique namely as cross laminated technique was considered where the walls is fabricated using two layers of 600 mm x 2400 mm x 50 mm thickness of WWCP strips, where each layer consists of four panel strips that were arranged at cross wise panel orientation. The front and rear panel strips were bonded together using 15 mm thickness of mortar paste and as a finishing 16 mm thickness of mortar base plaster were applied on both surfaces. The prefabricated wall specimens were tested under axial compression load up to failure after 28 days of curing period. The axial load carrying capacity, vertical and lateral displacement and failure mode behaviour of walls were observed during and after test conducted. The results of experimental testing recorded that; the maximum axial compression load of prefabricated wood-wool wall specimens achieved the capacity of 1038.54 kN. This shows that the new prefabricated wall constructed using cross laminated wood-wool panel can be used as a load bearing wall system for low rise building
Simulation of shear and bending cracking in RC beam: material model and its application to impact
This paper presents a simple and reliable non-linear numerical analysis incorporated
with fully Lagrangian method namely Smoothed Particle Hydrodynamics (SPH) to predict the
impact response of the reinforced concrete (RC) beam under impact loading. The analysis
includes the simulation of the effects of high mass low-velocity impact load falling on beam
structures. Three basic ideas to present the localized failure of structural elements are: (1) the
accurate strength of concrete and steel reinforcement during the short period (dynamic), Dynamic
Increase Factor (DIF) has been employed for the effect of strain rate on the compression and
tensile strength (2) linear pressure-sensitive yield criteria (Drucker-Prager type) with a new
volume dependent Plane-Cap (PC) hardening in the pre-peak regime is assumed for the concrete,
meanwhile, shear-strain energy criterion (Von-Mises) is applied to steel reinforcement (3) two
kinds of constitutive equation are introduced to simulate the crushing and bending cracking of
the beam elements. Then, these numerical analysis results were compared with the experimental
test results
Influence of traffic vehicles against ground fundamental frequency prediction using ambient vibration technique
Ambient vibration (AV) technique is widely used nowadays for ground fundamental
frequency prediction. This technique is easy, quick, non-destructive, less operator required and
reliable result. The input motions of ambient vibration are originally collected from
surrounding natural and artificial excitations. But, careful data acquisition controlled must be
implemented to reduce the intrusion of short period noise that could imply the quality of
frequency prediction of an investigated site. In this study, investigation on the primary noise
intrusion under peak (morning, afternoon and evening) and off peak (early morning) traffic
flows (only 8 meter from sensor to road shoulder) against the stability and quality of ground
fundamental frequency prediction were carried out. None of specific standard is available for
AV data acquisition and processing. Thus, some field and processing parameters recommended
by previous studies and guideline were considered. Two units of 1 Hz tri-axial seismometer
sensor were closely positioned in front of the main entrance Universiti Tun Hussein Onn
Malaysia. 15 minutes of recording length were taken during peak and off peak periods of
traffic flows. All passing vehicles were counted and grouped into four classes. Three
components of ambient vibration time series recorded in the North-South: NS, East-West: EW
and vertical: UD directions were automatically computed into Horizontal to Vertical Spectral
Ratio (HVSR), by using open source software of GEOPSY for fundamental ground frequency,
Fo determination. Single sharp peak pattern of HVSR curves have been obtained at peak
frequencies between 1.33 to 1.38 Hz which classified under soft to dense soil classification.
Even identical HVSR curves pattern with close frequencies prediction were obtained under
both periods of AV measurement, however the total numbers of stable and quality windows
selected for HVSR computation were significantly different but both have satisfied the
requirement given by SESAME (2004) guideline. Besides, the second peak frequencies from
the early morning HVSR curve was clearly indicated between 8.23 to 8.55 Hz at very low
amplitude (Ao < 2), but it should be neglected according to the similar guideline criteria. In
conclusion, the ground fundamental frequency using HVSR method was successfully
determined by 1 Hz seismometer instrument with recommended to specific parameters consideration on field as well as data processing, without disruption from the nearest traffic
excitations
Structural health monitoring on medium rise reinforced concrete building using ambient vibration method
Monitoring of structural health from initial stage of building construction to its
serviceability is an ideal practise to assess for any structural defects or damages. Structural
integrity could be intruded by natural destruction or structural deterioration, and worse if
without remedy action on monitoring, building re-assessment or maintenance is taken. In this
study the application of ambient vibration (AV) testing is utilized to evaluate the health of
eighth stories medium rise reinforced concrete building in Universiti Tun Hussein Onn
Malaysia (UTHM), based comparison made between the predominant frequency, fo,
determined in year 2012 and 2017. For determination of fo, popular method of Fourier
Amplitude Spectra (FAS) was used to transform the ambient vibration time series by using 1
Hz tri-axial seismometer sensors and CitySharkII data recorder. From the results, it shows the
first mode frequencies from FAS curves indicate at 2.04 Hz in 2012 and 1.97 Hz in 2017 with
only 3.14% of frequency reduction. However, steady state frequencies shown at the second and
third modes frequencies of 2.42 Hz and 3.31 Hz by both years. Two translation mode shapes
were found at the first and second mode frequencies in the North-South (NS-parallel to
building transverse axis) and East-West (EsW-parallel to building longitudinal axis)
components, and the torsional mode shape shows as the third mode frequency in both years.
No excessive deformation amplitude was found at any selective floors based on comparison
made between three mode shapes produced, that could bring to potential feature of structural
deterioration. Low percentages of natural frequency disparity within five years of duration
interval shown by the first mode frequencies under ambient vibration technique was considered
in good health state, according to previous researchers recommendation at acceptable
percentages below 5 to 10% over the years
Polypyrrole-Fe2O3 nanohybrid materials for electrochemical storage
We report on the synthesis and electrochemical characterization of nanohybrid polypyrrole (PPy) (PPy/Fe2O3) materials for electrochemical storage applications. We have shown that the incorporation of nanoparticles inside the PPy notably increases the charge storage capability in comparison to the “pure” conducting polymer. Incorporation of large anions, i.e., paratoluenesulfonate, allows a further improvement in the capacity. These charge storage modifications have been attributed to the morphology of the composite in which the particle sizes and the specific surface area are modified with the incorporation of nanoparticles. High capacity and stability have been obtained in PC/NEt4BF4 (at 20 mV/s), i.e., 47 mAh/g, with only a 3% charge loss after one thousand cyles. The kinetics of charge–discharge is also improved by the hybrid nanocomposite morphology modifications, which increase the rate of insertion–expulsion of counter anions in the bulk of the film. A room temperature ionic liquid such as imidazolium trifluoromethanesulfonimide seems to be a promising electrolyte because it further increases the capacity up to 53 mAh/g with a high stability during charge–discharge processes
Colours Effect Analysis on The Attention Level with A Single-Channel EEG
Colours play an important role in many applications such as in education, communication, tourism, marketing, and architecture. From the previous research, especially related to education, colour could affect people's focus or attention level. However, with further investigation, the colour could also be used for controlling or activating electronic devices. Therefore, the purpose of this study is to find out if turquoise, green, red, and a combination of red, orange, and yellow (picture of autumn) could trigger the attention level to be equal to or above the attention threshold. The required threshold that had been decided was 40. The attention level of five (5) respondents was recorded when they were looking at the colours for 8 seconds using a single-channel EEG of the Neurosky Mindwave headset. From the study, it is found that all colours could trigger the attention level of all respondents to be above the attention threshold of 40. However, the combination of red, orange, and yellow (autumn picture) showed the best result in triggering or maintaining the attention value within 40 to 100. The colour could be a potential input in controlling electronic devices that have an attention threshold of 40
Isolation of Flow and Nonflow Correlations by Two- and Four-Particle Cumulant Measurements of Azimuthal Harmonics in 200 GeV Au+Au Collisions
A data-driven method was applied to measurements of Au+Au collisions at
200 GeV made with the STAR detector at RHIC to isolate
pseudorapidity distance -dependent and -independent
correlations by using two- and four-particle azimuthal cumulant measurements.
We identified a component of the correlation that is -independent,
which is likely dominated by anisotropic flow and flow fluctuations. It was
also found to be independent of within the measured range of
pseudorapidity . The relative flow fluctuation was found to be for particles of transverse momentum
less than GeV/. The -dependent part may be attributed to
nonflow correlations, and is found to be relative to the
flow of the measured second harmonic cumulant at
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