School of Engineering, Computer and Mathematical Sciences - Te Kura Mātai Pūhanga, Rorohiko, Pāngarau

Permanent link for this collection

http://hdl.handle.net/10292/553
AUT is home to a number of renowned research institutes in engineering, and computer and mathematical sciences. The School of Engineering, Computer and Mathematical Sciences strong industry partnerships and the unique combination of engineering, computer and mathematical sciences within one school stimulates interdisciplinary research beyond traditional boundaries. Current research interests include:
  • Artificial Intelligence; Astronomy and Space Research;
  • Biomedical Technologies;
  • Computer Engineering; Computer Vision; Construction Management;
  • Data Science;
  • Health Informatics and eHealth;
  • Industrial Optimisation, Modelling & Control;
  • Information Security;
  • Mathematical Sciences Research; Materials & Manufacturing Technologies;
  • Networking, Instrumentation and Telecommunications;
  • Parallel and Distributed Systems; Power and Energy Engineering;
  • Software Engineering; Signal Processing; STEM Education;
  • Wireless Engineering;

Browse

Recent Submissions

Now showing 1 - 5 of 1186
  • Item
    Systematic KMTNet Planetary Anomaly Search. VIII. Complete Sample of 2019 Subprime Field Planets
    (American Astronomical Society, 2023-05-04) Jung, YK; Zang, W; Wang, H; Han, C; Gould, A; Udalski, A; Zhu, W; Albrow, MD; Chung, SJ; Hwang, KH; Ryu, YH; Shin, IG; Shvartzvald, Y; Yang, H; Yee, JC; Cha, SM; Kim, DJ; Kim, SL; Lee, CU; Lee, DJ; Lee, Y; Park, BG; Pogge, RW; Maoz, D; Szymański, MK; Skowron, J; Poleski, R; Soszyński, I; Pietrukowicz, P; Kozłowski, S; Ulaczyk, K; Rybicki, KA; Iwanek, P; Wrona, M; Porritt, I; Green, J; Hennerley, S; Marmont, A; Mao, S; Natusch, T; Penny, MT; Natusch, T
    We complete the publication of all microlensing planets (and “possible planets”) identified by the uniform approach of the KMT AnomalyFinder system in the 21 KMT subprime fields during the 2019 observing season, namely, KMT-2019-BLG-0298, KMT-2019-BLG-1216, KMT-2019-BLG-2783, OGLE-2019-BLG-0249, and OGLE-2019-BLG-0679 (planets), as well as OGLE-2019-BLG-0344 and KMT-2019-BLG-0304 (possible planets). The five planets have mean log mass ratio measurements of (−2.6, −3.6, −2.5, −2.2, −2.3), median mass estimates of (1.81, 0.094, 1.16, 7.12, 3.34) M Jup, and median distance estimates of (6.7, 2.7, 5.9, 6.4, 5.6) kpc, respectively. The main scientific interest of these planets is that they complete the AnomalyFinder sample for 2019, which has a total of 25 planets that are likely to enter the statistical sample. We find statistical consistency with the previously published 33 planets from the 2018 AnomalyFinder analysis according to an ensemble of five tests. Of the 58 planets from 2018-2019, 23 were newly discovered by AnomalyFinder. Within statistical precision, half of the planets have caustic crossings, while half do not; an equal number of detected planets result from major- and minor-image light-curve perturbations; and an equal number come from KMT prime fields versus subprime fields.
  • Item
    Structural Optimisation for Controlled Deflections of Additively Manufactured Single Material Beams
    (Nature Portfolio, 2023-04-28) Yang, Wuxin; Behera, Malaya Prasad; Lv, Yifan; Huang, Loulin; Singamneni, Sarat
    Closely controlling the mechanical behaviour and characterization of the deflection of a beam structure is a well-known and widely studied engineering problem. The progress in additive manufacturing methods and the possibilities to closely control the material property variations with the controlled placement of materials further widen the opportunities to achieve given beam deflection criteria. The multi-material additive manufacturing solutions suffer from the lack of real engineering material options, and the quality and performance of the printed parts are usually unsuitable for producing functional parts. A novel cellular structured solution is proposed here, which utilises optimisation of geometries of individual cells of a single material structured beam to obtain deflection profiles closely matched with preset conditions under different loading conditions. The cellular geometry of the structured beam is continually altered for searching and converging on the optimal structure of the cells by the covariance matrix adaptation evolution strategy algorithm in an iterative manner. The optimised beam structures could also be physically produced with single material additive manufacturing methods and the experimental and numerical beam deflection responses correlated closely.
  • Item
    Experimental Evaluation of a Novel Stability Control System for Two-Wheeled Robotic Wheelchairs
    (Elsevier BV, 2023-05-26) Nikpour, Mostafa; Huang, Loulin
    A conventional robotic wheelchair containing four wheels (two active driving wheels and two passive casters) is statically stable with poor manoeuvrability. In comparison, a two-wheeled robotic wheelchair (TWRW) without the support of casters offers much better manoeuvrability but is inherently unstable and requires a stability control. Most stability controllers rely on the driving torques of the wheels which are high in magnitude and result in large energy consumption. Various disturbances in the system also affect the performance of the controller. To address these problems, this paper presents a novel control approach where the stability control is achieved through the motion of a pendulum-like movable mechanism added to the TWRW. A scaled-down TWRW is designed to evaluate the performances of the controllers based on PID control and second order sliding mode control (SOSMC). Experimental results show that under the proposed controller approach, the stability of the TWRW is achieved with much less torque, power, and energy consumption than the conventional control systems.
  • Item
    An Overview of Enhancing the Performance of Medical Implants with Nanocomposites
    (MDPI AG, 2023-05-15) Ramezani, Maziar; Ripin, Zaidi Mohd
    Medical implants are essential tools for treating chronic illnesses, restoring physical function, and improving the quality of life for millions of patients worldwide. However, implant failures due to infection, mechanical wear, corrosion, and tissue rejection continue to be a major challenge. Nanocomposites, composed of nanoparticles or nanofillers dispersed in a matrix material, have shown promising results in enhancing implant performance. This paper provides an overview of the current state of research on the use of nanocomposites for medical implants. We discuss the types of nanocomposites being developed, including polymer-, metal-, and ceramic-based materials, and their advantages/disadvantages for medical implant applications. Strategies for improving implant performance using nanocomposites, such as improving biocompatibility and mechanical properties and reducing wear and corrosion, are also examined. Challenges to the widespread use of nanocomposites in medical implants are discussed, such as biocompatibility, toxicity, long-term stability, standardisation, and quality control. Finally, we discuss future directions for research, including the use of advanced fabrication techniques and the development of novel nanocomposite materials. The use of nanocomposites in medical implants has the potential to improve patient outcomes and advance healthcare, but continued research and development will be required to overcome the challenges associated with their use.
  • Item
    Analysis of Improved In-Cylinder Combustion Characteristics with Chamber Modifications of the Diesel Engine
    (MDPI AG, 2023-03-09) Doppalapudi, AT; Azad, AK; Khan, MMK
    This study numerically analyses the effects of chamber modifications to investigate the improvement of in-cylinder combustion characteristics of the diesel engine using a computational fluid dynamics (CFD) approach. Five different modified chambers, namely, the double swirl combustion chamber (DSCC), bathtub combustion chamber (BTCC), double toroidal re-entrant combustion chamber (DTRCC), shallow depth combustion chamber (SCC), and stepped bowl combustion chamber (SBCC) were developed and compared with a reference flat combustion chamber (FCC). The effects of chamber modifications on temperature formation, velocity distribution, injection profiles, and in-cylinder turbulent motions (swirl and tumble ratio) were investigated. During the compression stroke, near top dead centre, the SCC showed a peak temperature of 970 K, followed by the FCC (968 K), SBCC (967 K), and DTRCC (748 K to 815 K). The DSCC and the SCC showed a high swirl ratio above 0.6, whereas the DTRCC and the BTCC showed a high tumble ratio of approximately 0.4. This study found that the SCC, BTCC, and DSCC have better combustion rates than the FCC in terms of temperature, heat release rate, and velocity distribution. However, the DTRCC showed poor temperature formation rates and rapid heat release rates (approx. 150 J/°CA), which can lead to rapid combustion and knocking tendencies. In conclusion, the DSCC and the SCC showed better combustion rates than the other chambers. In addition, turbulent motions inside the chambers avoided combustion in crevice regions. This study recommends avoiding chambers with wider bowls in order to prevent uneven combustion across the cylinder. Furthermore, split bowls such as the DSCC, along with adjusted injection rates, can provide better results in terms of combustion.
Items in these collections are protected by the Copyright Act 1994 (New Zealand). These works may be consulted by you, provided you comply with the provisions of the Act and the following conditions of use:
  • Any use you make of these works must be for research or private study purposes only, and you may not make them available to any other person.
  • Authors control the copyright of their works. You will recognise the author’s right to be identified as the author of the work, and due acknowledgement will be made to the author where appropriate.
  • You will obtain the author’s permission before publishing any material from the work.