8,219 research outputs found
Line and wall follower hexapod robot
Robot widely use to help human to do something, especially for difficult or
danger task. To fulfil the robot requirements, some techniques, sensors and controller
have been applied. Due to kind of robot is a hexapod robot, which it develops in this
research. Hexapod robot is a mechanical vehicle that’s walk on 6 legs. A hexapod
robot movement are guided with guidance, they are line and wall. Fuzzy logic
control as intelligent control is applied to govern the robot follow line and wall.
Fuzzy logic controller is used to create a smooth response of robot behaviour rather
than logic programming. Infrared sensors are used to sense line and distance to the
wall as the input variable for the controller. Based on these signals, the controller
control the turning angle of forward movement thus making robot to move forward
and turning in same time
Genetic Algorithm-based Robot Path Planning
Nowadays, building an intelligent robot that able to move by itself from one location to another without collides with other obstacles is of interest in many applications. In the real world, condition of an environment is always unpredictable and changes with the existence of dynamic obstacles. This paper tends to propose an algorithm for robot path planning in a dynamic environment using Genetic algorithm (GA) technique. The proposed algorithm is able to find an optimum path for a robot and avoid any static and dynamic obstacles. The variation of the proposed algorithm is shown with the implementation of the algorithm in 4-way movement robot and 8-way movement robot. The simulation results show significant performance of the algorithm when compared with real optimum path
Sea surface temperature retrieval using TRMM microwave imager satellite data in the South China Sea
The passive microwave TRMM Microwave Imager (TMI) sensor which is one of the payloads of the Tropical Rainfall Measurement Mission (TRMM) satellite was launched in 1997 by the National Aeronautics and Space Administration (NASA) and National Space Development Agency of Japan (NASDA). The TMI provides daily maps, 3 day average, weekly and monthly binary data via internet that can be used to retrieve geophysical parameters such as sea surface temperature (SST), 10 meter surface wind speed using 11 GHz channel, 10 meter surface wind speed using 37 GHz channel, atmospheric water vapour, liquid cloud water and precipitation rates. The SST study over the South China Sea was carried out using the 10.7 GHz channel of the TMI. The advantage of using this data is that the SST can be measured through clouds that are nearly transparent on this channel. This is a distinct advantage over the traditional infrared SST observations that require a cloud-free field of view. In this study, multitemporal TMI binary data were processed using FORTRAN Programming Language to evaluate the SST variations with time over the study area. The 3-day, weekly and monthly binary files are similar to the daily TMI binary files. All data consists of six maps with grid size of 0.25o by 0.25o and each file can be read as a 1440, 320, 6 array. For the data processing, the data values fall between 0 and 250 that need to be scaled to obtain meaningful geophysical data. The TMI scanning system causes striping that contains 0 or invalid data. In-situ temperature values were taken at locations where useful satellite data are available i.e. no striping. Regression analysis was carried out using the SST from TMI data and in-situ data obtained from the Meteorological Department of Malaysia. The two-dimensional scatter plot between TMI data and in-situ data gives a R2 value of 0.92 and RMSE of 0.3oC. The SST during the north east monsoon period was slightly lower than the SST during the south west monsoon. The study shows that TMI satellite data can be used to derive SST over large areas of the sea
Kebolehacuanan suntikan logam mikro SS 316L menggunakan bahan pengikat PEG dan PMMA Mohd
Pengacuanan suntikan logam mikro atau lebih dikenali µMIM merupakan satu proses
yang berkesinambungan daripada proses penyuntikan logam. Proses ini menggunakan
serbuk logam bersaiz mikro dan mampu menghasilkan produk mikro yang kompleks
pada kuantiti yang banyak serta yang memerlukan kepersisan permukaan yang tinggi
dan jitu. Penggunaan saiz serbuk logam mikro akan meningkatkan nilai kelikatan
bahan suapan yang mana ia merupakan cabaran utama di dalam proses µMIM yang
akhirnya akan menyukarkan proses penyuntikan. Selain itu, ia juga akan meningkatkan
peratusan kadar pengecutan dan kandungan oksigen jasad sinter. Oleh itu, kajian ini
bertujuan untuk mengoptimumkan parameter setiap proses berdasarkan kepada teknik
Rekabentuk Eksperimen agar dapat menghasilkan jasad sinter yang berketumpatan
tinggi dan kuat, rendah kandungan oksigen, kurang kecacatan serta kadar pengecutan
yang minima. Bahan pengikat yang terdiri daripada 73vol% Polietilena Glikol (PEG),
25vol% Polimetil Metakrilate (PMMA) dan 2vol% Asid Stearik di campur dengan SS
316L bersaiz mikro bagi menghasilkan bahan suapan yang homogen dan sekata.
Analisis kebolehaliran bahan suapan dikaji melalui sifat reologinya pada suhu 130-
150°C iaitu suhu peleburan yang dicatatkan melalui ujian DSC. Pembebanan serbuk
pada 61.5% menunjukkan pembebanan yang paling optimum kerana ia menyumbang
kepada sifat pseudoplastik, kelikatan dan indeks tingkahlaku aliran yang sekata, nilai
tenaga pengaktifan yang rendah serta indeks kebolehacuan yang tinggi seperti mana
yang diperlukan di dalam µMIM. Analisis varian (ANOVA) dilakukan di dalam setiap
proses penyuntikan, penyahikatan larutan, penyahikatan terma dan pensinteran bagi
mengenal pasti parameter yang paling signifikan dan sumbangannya terhadap ciri
kualiti yang dikaji iaitu ketumpatan dan kekuatan lentur dengan hanya parameter
kajian melepasi aras keyakinan 90% sahaja yang diambil kira. Melalui ujian ANOVA
di dalam penyuntikan, 3 interaksi menunjukkan kesignifikan iaitu tekanan
penyuntikan, suhu penyuntikan dan suhu acuan manakala masa penyuntikan dan masa
pegangan dikekalkan sebagai parameter tunggal. Interaksi antara suhu penyuntikan dan
suhu acuan merupakan penyumbang terbesar di dalam kedua-dua kaedah tersebut.
Penyingkiran bahan pengikat sekunder iaitu PEG dilakukan melalui proses
penyahikatan larutan pada suhu 55-65°C dengan masa rendaman antara 2-6 jam.
ANOVA menunjukkan hanya 4 parameter yang signifikan di dalam proses ini iaitu
masa penyahikatan, suhu penyahikatan, masa penyuntikan dan tekanan penyuntikan
manakala tiada interaksi yang signifikan direkodkan di dalam proses ini. Analisis
pengoptimuman menggunakan kaedah Grey-Taguchi menunjukkan masa penyahikatan
adalah penyumbang terbesar diikuti oleh suhu penyahikatan iaitu sekitar 39%.
Disebabkan oleh pengendalian yang amat teliti diperlukan di dalam komponen mikro,
2 proses seterusnya telah digabungkan iaitu penyahikatan terma dan pensinteran
dengan menggunakan relau vakum bagi mengelakkan sebarang pengoksidaan berlaku.
Bagi kedua-dua proses ini, 6 parameter dikenalpasti signifikan iaitu suhu pensinteran,
masa pensinteran, kadar pensinteran, suhu penyahikatan, masa penyahikatan dan kadar
penyahikatan dengan 3 interaksi diambilkira pada tatacara ortogonal L27(313). Melalui
kaedah pengoptimuman Grey-Taguchi ini, kekuatan dan ketumpatan jasad sinter
berjaya ditingkatkan sehingga 96.79% daripada ketumpatan piknometer. Di samping
itu juga, proses pengoptimuman ini juga berjaya meminimakan kadar pengecutan jasad
sinter sehingga 11.75% berbanding kajian oleh penyelidik terdahulu yang mana ia
berada diantara 16-20%. Kandungan oksigen juga dapat diminimakan sekitar 2300
ppm iaitu di dalam julat yang dibenarkan oleh piawaian ASTM E101
A New Digital Watermarking Algorithm Using Combination of Least Significant Bit (LSB) and Inverse Bit
In this paper, we introduce a new digital watermarking algorithm using least
significant bit (LSB). LSB is used because of its little effect on the image.
This new algorithm is using LSB by inversing the binary values of the watermark
text and shifting the watermark according to the odd or even number of pixel
coordinates of image before embedding the watermark. The proposed algorithm is
flexible depending on the length of the watermark text. If the length of the
watermark text is more than ((MxN)/8)-2 the proposed algorithm will also embed
the extra of the watermark text in the second LSB. We compare our proposed
algorithm with the 1-LSB algorithm and Lee's algorithm using Peak
signal-to-noise ratio (PSNR). This new algorithm improved its quality of the
watermarked image. We also attack the watermarked image by using cropping and
adding noise and we got good results as well.Comment: 8 pages, 6 figures and 4 tables; Journal of Computing, Volume 3,
Issue 4, April 2011, ISSN 2151-961
Optical Waveguide Modelling Based On Scalar Finite Difference Scheme
A Numerical Method Based On Scalar Finite Difference Scheme Was Adopted And Programmed On MATLAB® Platform For Optical Waveguide Modeling Purpose. Comparisons With Other Established Methods In Terms Of Normalized Propagation Constant Were Included To Verify Its Applicability. The Comparison Results Obtained Were Proven To Have The Same Qualitative Behaviour. Furthermore, The Performances Were Evaluated In Terms Of Computation Complexity, Mesh Size, And Effect Of Acceleration Factor. Computation Complexity Can Be Reduced By Increasing The Mesh Size Which Will Then Produce More Error. The Problem Can Be Rectified By Introducing The Acceleration Factor, Successive Over Relaxation (SOR) Parameter. It Shows That SOR Range Between 1.3 And 1.7 Can Give Shorter Computation Time, While Producing Constant Value Of Simulation Results
Polymer optical waveguide based n wet-chemical fabrication process
The wet-chemical fabrication process of BenzoCyclobutene (BCB 4024-40) polymer waveguides are described. The method of prism coupling is adopted in the characterization process of the polymer film. A cost effective chemical etching technique is used in the waveguide fabrication process to take advantage of the photosensitive nature of the polymer. The waveguide loss is measured using the conventional cut back method which results on an average loss of 3.5 dB/cm
Competition, non-financial measures and the effectiveness of management control system
This paper reports the results of an empirical study examining the relationship between the emphasis on non-financial measures and two other variables; the intensity of competition and the effectiveness of a management control system, in a manufacturing company. Two important issues focused in the study are: does competition compel managers to utilize more non-financial measures in decision making and is the emphasis given to non-financial measures worthwhile? Data from 105 manufacturing companies throughout Malaysia were analyzed using correlation and regression analysis. The results of both analyses indicate that the emphasis given to non-financial measures in decision making has a positive correlation with the effectiveness of a management control system and secondly, the intensity of competition faced by an organization is positively correlated with the emphasis on non-financial indicators. Descriptive analysis was also performed to evaluate the distribution of emphasis on non-financial measures by the age, location, ownership, size of an organization and its industry
The performance of students in university subjects at UTM’s
TITAS has been introduced in the university curriculum as one of the general subjects/courses that all students are required to take. At UTM’s franchised centres, it has been discovered that many students have obtained very poor grades for this subject. The reasons for the poor performance had to be determined and this study attempted to discover the main reasons why students performed badly in the subject. The study found that among others it was a problem of attitudes both on the part of the teacher as well as the student besides communication problems between UTM and its franchised centres that contributed to the problem
A Review on Biological Inspired Computation in Cryptology
Cryptology is a field that concerned with cryptography and cryptanalysis. Cryptography, which is a key technology in providing a secure transmission of information, is a study of designing strong cryptographic algorithms, while cryptanalysis is a study of breaking the cipher. Recently biological approaches provide inspiration in solving problems from various fields. This paper reviews major works in the application of biological inspired computational (BIC) paradigm in cryptology. The paper focuses on three BIC approaches, namely, genetic algorithm (GA), artificial neural network (ANN) and artificial immune system (AIS). The findings show that the research on applications of biological approaches in cryptology is minimal as compared to other fields. To date only ANN and GA have been used in cryptanalysis and design of cryptographic primitives and protocols. Based on similarities that AIS has with ANN and GA, this paper provides insights for potential application of AIS in cryptology for further research
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