15,768 research outputs found
Antilock braking control using robust control approach
The aims of this study are to establish the mathematical model and the robust control technique for an Antilock Braking System (ABS). The ABS have been developed to reduce tendency of wheel lock up and to improve vehicle control during sudden braking. The ABS work by maintaining the wheel slip to a desired level so that maximum tractive force and maximum vehicle deceleration is obtained, thus reducing the vehicle stopping distance. A quarter vehicle model undergoing straightline braking maneuver, tire dynamics and hydraulic brake dynamics mathematical model are developed to represent the ABS model. The established mathematical model shows the ABS dynamics exhibits strong nonlinear characteristics. Thus, Sliding Mode Control which is a robust control technique is proposed in this study to regulate the wheel slip at the desired value depending on the road surface. The mathematical derivations proved the designed controller satisfy the stability requirement. Extensive simulation study is performed to verify the effectiveness of the designed controller and the result shows the designed controller able to maintain the wheel slip at the desired value and reducing the stopping distanc
The age-structured population models : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Mathematics at Massey University
Mathematical theories of population dynamics have been derived and have been effectively used in the last two hundred years. These theories have appeared both implicitly and explicitly in many important studies of populations: human populations, as well as populations of animals, cells and viruses. The aim of this thesis is to understand how these models have developed with a view to an improved formulation. Nowadays, the structured model can be considered to be of great importance and use. Mathematicians have realised that in real biological and ecological situations, a model should be developed which is at least structured on age especially with higher order animals, for example human and possum populations, so in this thesis we pay much attention to these type of population models. We shall also be discussing the qualitative nature of the solutions to the model: such as the long-term behaviour, steady-age distribution and the stability of the solution in great details. In chapter 1, we begin with the historical background of the unstructured population in which the properties of individuals are ignored and only the total population is considered. The Malthusian and Verhulst model are set as examples. We then proceed in chapter 2 with the simplest McKendrick's age- structured population model. In chapter 3, we shall show how Laplace transform can be used to solved the problem. We have also chosen some arbitrary functions for either one or both the birth and/or death rate, so that we can make deductions from the assumption of these special cases. Chapter 4, discusses the long-term behaviour: steady age distribution (s.a.d.) and the stability of the solution being analysed. We then generalise the linear age- dependent population model in chapter 5 to a non-linear age-dependent model where the limiting effects (overcrowding and limitation of resources) has an effect, on the specific age class only. Chapter 6 discusses the more realistic non-linear model similar to that described in chapter 5 but here the limiting effects have an effect on the whole population. Finally, we realise that since these models need to be tested, we shall, in chapter 7 test our model with possum populations on data collected from the Orongorongo Valley in Wellington. And then make suggestions for future work in Chapter 8
Effect of gap lenghts of sphere-sphere electrodes on air breakdown level under lightning impulse
Impinging jets are a best method of achieving particularly high heat transfer
coefficient and are therefore employed in many engineering applications. In this
study we seek to understand the mechanism of the distributed heat on the curve
surface with the goal of identifying preferred methods to predicting jet performance.
The goals that have been achieved in the numerical results displayed are
determine the influence of impingement jet characteristics on thermal and flow field
on a curve surface, determine the variation of Nusselt numbers (NuD) along the
curve surface in order to understand the heat transfer characteristics and study the
effect of position (in the center, in the mid and in the end) and angle (α=90°, 60° and
30°) of jet impingement on curve surface, different Reynolds numbers (ReD) in
range of (5000, 6000, 7000, 8000 and 9000). The program, which was extracted
results it is (GAMBIT 2.4.6) and (FLUENT 6.3), simulation is (2-D) in submerged
jet flow and the continuity, momentum and energy equations were solved by means
of a finite volume method (FVM).
This study covers the effect of different Reynolds numbers (ReD) on average
Nusselt numbers (Nuavg) and local Nusselt numbers (NuD). From the result, the
average Nusselt numbers (Nuavg) increased with the increase of Reynolds numbers
(ReD) for all cases, in comparison between different positions (center, mid and end),
of nozzle on curve surface at angle (α=90°) the maximum value of average Nusselt
numbers (Nuavg=388.3) is found when the nozzle locate in the end followed by the
mid position and smallest value of average Nusselt numbers (Nuavg=182.25) in the
center of curve surface. In case of slant angle (α=60º) the maximum value of average
Nusselt numbers (Nuavg=387.47) is found when the nozzle locate in the end
followed by the mid position and smallest value of average Nusselt numbers
(Nuavg=308.3) in the center of curve surface
Characterisation of ionospheric TEC variations over the equatorial and polar regions during solar cycle 24
The TEC variations in the equatorial and polar region are known to be high compared to the mid latitude region. Investigation on ionospheric TEC at individual regions has been carried out by many studies but the investigation between these regions simultaneously is still lacking. TEC values from Libreville (NKLG), Gabon (0.4162°N, 9.4673°E), and Ny-Alesund (NYA1), Norway (78.9235°N, 11.9099°E), each representing equatorial and polar station, respectively, are obtained for the year 2009, 2011, and 2013 to observe their TEC behaviors. The diurnal and seasonal variations of TEC and geomagnetic effects on TEC variations are analyzed for both stations. Besides, the rate of TEC change, K, is obtained to relate the TEC variations between these locations simultaneously. The pseudo-TEC measurement measured by dual frequency GPS which can be obtained from IGS server, is used to calculate vertical TEC. The ranges of maximum diurnal TEC at NKLG and NYA1 station is 23-114 TECU and 8-55 TECU, respectively. The seasonal TEC peak at both stations encountered the highest TEC at equinoctial months and the lowest value at solstitial months. However, in 2009, the seasonal TEC showed the highest and lowest TEC peak, both at equinoctial months at NYA1 station. During geomagnetic days, the enhancement percentages of TEC are found on 22 July 2009 and 17 March 2013 at NKLG station, and 22 July 2009 and 25 October 2011 at NYA1 station. The decrement percentage of TEC observed on 25 October 2011 and 17 March 2013 at NKLG and NYA1 station, respectively. The rate of TEC change shows a same definite pattern over all the years. It can be concluded that the hourly maximum TEC values at NKLG station fell within 0.4-1.9 times larger than that NYA1 station. This study helps to have more understanding of the unique characteristics at the equatorial and polar ionosphere
WCDMA in Malaysia
Wideband Code Division Multiple Access (WCDMA) A 3G highspeed digital data service provided by cellular carriers that use the time division multiplexing (TDMA) or GSM technology worldwide, including AT&T (formerly Cingular) and T-Mobile in the U.S. WCDMA works on WCDMA cell phones as well as laptops and portable devices with WCDMA modems [1]. Users have typically experienced downstream data rates up to 400 Kbps [1]. WCDMA has been used in the Japanese Freedom of Mobile Multimedia Access (FOMA) system and in the Universal Mobile Telecommunications System (UMTS); a third generation follow-on to the 2G GSM networks deployed worldwide [1]. Although TDMA and GSM carriers both use TDMA modulation, WCDMA stems from CDMA. Part of the 3GPP initiative, the International Telecommunication Union (ITU) refers to WCDMA as the Direct Sequence (DS) interface within the IMT-2000 global 3G standards [1]
Pengaruh penerapan model pembelajaran role playing terhadap aktifitas guru dan hasil belajar dalam mata pelajaran pendidikan IPS di sekolah dasar
Belajar dengan menggunakan role playing meningkatkan kesadaran akan adanya hubungan antara yang diperankan dengan masalah kehidupan masyarakat yang sebenarnya. Secara empirik, pernyataan ini memang sulit diamati karena hanya bersifat ungkapan secara verbal dari responden siswa. Bagaimana bentuk kesadaran itu, tidak mudah diketahui oleh penulis maupun oleh guru kelas sebagai mitra peneliti. Namun demikian, dari pernyataan itu penulis dapat menangkap kesan bahwa,tindakan pembelajaran dengan model role playing ternyata dapat memenuhi salah satu asumsi penggunaannya, yaitu sebagai model yang dirancang
untuk mengembangkan empati siswa terhadap orang lain
dan mengorganisasikan isu-isu sosial. Lebih jauh, pernyataan siswa tersebut mengisyaratkan pula bahwa model pembelajaran role playing memiliki signifikansi dengan tujuan-tujuan pembelajaran yang berdomain afektual. Hal ini sejalan dengan watak khas Pendidikan IPS di SD khususnya yang berkaitan dengan nilai dan sikap yang memungkinkan anak berpartisipasi dalam kelompoknya, baik kelompok utama dalam keluarga dan sekolah maupun kelompok sosial yang lebih luas
THE ART OF RHETORIC USING STYLISTIC DEVICES IN WORLD UNIVERSITIES DEBATING CHAMPIONSHIP: A Study of Pragmatics
Debating is recognized as a way of doing persuasion in speech that deals with four points of
debate pillars, for instance: assertion, reasoning, evidence, and link back. There are two
formats on parliamentary debating competitions; Asian and British. The format of worlds is
British Parliamentary debate, which consists of eight debaters divided into four teams, two on
the pro-position and other two on the opposition, and allows debaters 15 minutes of preparation
and doing the case building before engaging in the round (Harvey-Smith, 2011; Johnson, 2009;
Lising, 2010). Over past few years, every country’s debater champions have been gathered and
involved in a high level of debate atmosphere to compete each other as their country’s
representatives to have worlds’ champion title. In conjunction to the glance of forewords,
researcher will analyze annual world most prestigious debating championship, WUDC 2016,
which took place in Thessaloniki, Greece. The study will use descriptive qualitative method. The
source of this research is taken from video streaming on Youtube that shows ESL grand final
round between University of Indonesia team A (Indonesia) as Prime Minister (PM) and RWTH
Aachen team A (Germany) as leader of opposition (LO). This approach is intended to answer:
(1) What stylistic devices appear in World Universities Debating Championship 2016? (2) What
kinds of illocutionary act appear and how its perlocutionary impacts the opponent side’s
respond that results in rebuttal? This analysis is based on Aristotle (1991) and Searle (1979)
which result is expected to reveal the technique of how debaters unconsciously deliver their
persuasive speech in front of adjudicator core
Upaya peningkatan aktivitas siswa dalam pembelajaran PKN dengan menggunakan model pembelajaran kooperatif jigsaw
Pendidikan Kewarganegaraan menuntut siswa menunjukkan sikap yang baik, kreatif, dan bertanggungjawab. Tapi kenyataan di lapangan menunjukkan bahwa tujuan pembelajaran PKn belum tercapai sebagaimana yang diharapkan. Seringkali guru menemukan siswa tidak berani mengemukakan pendapat maupun bertanya. Dalam bekerja kelompok banyak dari anggota kelompok yang hanya mencantumkan nama saja tanpa ikut berpartisipasi dalam kelompok. Tanggungjawab siswa rendah, baik terhadap dirinya sendiri (individu) maupun terhadap kelompok. Penelitian ini dilakukan di kelas VII B, semester 2, tahun pelajaran 2007/2008 di SD N 008 Malinau Kota. Tujuan dari penelitian ini untuk meningkatkan aktivitas siswa dalam pembelajaran PKn. Jenis penelitian yang digunakan adalah Penelitian Tindakan Kelas (PTK) yang terdiri dari dua siklus dan setiap siklus terdiri dari dua kali pertemuan. Alat pengumpul data yang digunakan adalah lembaran observasi, catatan lapangan, dan kuesioner
Measuring volume of stockpile using imaging station
It is crucial to know cutting and filling volumes in many surveys, mining, quarry and engineering field of works like dredging and embankment project. Generally, volume calculation is completed using conventional surveying methods. The trapezoidal method and classical cross sectioning have been presented in the literature. In other way around, by using conventional surveying methods, the volume calculation required a lot of time, laborers and risky as the big machineries running around the work areas. Digital close range photogrammetry has been insufficient for the volume calculation of the material need to calculation of volume in risk areas or in short time. In this case, long range surveying and scanning method is an alternative method to volume calculation. By the development of scanning and imaging technologies, Topcon Imaging Station (IS) used for three dimensional modeling (3D) surveying of objects in many field such as topographic survey, mining, construction and as-built survey, etc disciplines has become a productive, faster and accurate method. This study concern is getting the stockpile volume by using Topcon IS known as advanced technology instrument which promotes both scanning and long-range surveying. The instrument, a highly-developed technology specialized with Image Master Software; distinctive software that provides capabilities to reconstructed 3D modeling after the volume data was processed. Three dimensional (3D) surfaces are created through Triangulated Irregular Network (TIN) method that supports time saving and more accurate volume calculation. The volume calculated by Image Master (IM) then compared with the volume calculated by 12D software which the data obtained by using total station and prism. The results have been analyzed with respect to different volumes, density factor, three dimensional (3D) models of stockpile and time taken for data acquisition and data processin
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