1,843 research outputs found
sj-docx-1-qjp-10.1177_17470218221079269 – Supplemental material for Are there task-specific effects in morphological processing? Examining semantic transparency effects in semantic categorisation and lexical decision
No full textSupplemental material, sj-docx-1-qjp-10.1177_17470218221079269 for Are there task-specific effects in morphological processing? Examining semantic transparency effects in semantic categorisation and lexical decision by Qian Wen Chee and Melvin J Yap in Quarterly Journal of Experimental Psychology</p
Soft Subdivision Motion Planning for Complex Planar Robots
No full textThe design and implementation of theoretically-sound robot motion planning algorithms is challenging. Within the framework of resolution-exact algorithms, it is possible to exploit soft predicates for collision detection. The design of soft predicates is a balancing act between easily implementable predicates and their accuracy/effectivity.
In this paper, we focus on the class of planar polygonal rigid robots with arbitrarily complex geometry. We exploit the remarkable decomposability property of soft collision-detection predicates of such robots. We introduce a general technique to produce such a decomposition. If the robot is an m-gon, the complexity of this approach scales linearly in m. This contrasts with the O(m^3) complexity known for exact planners. It follows that we can now routinely produce soft predicates for any rigid polygonal robot. This results in resolution-exact planners for such robots within the general Soft Subdivision Search (SSS) framework. This is a significant advancement in the theory of sound and complete planners for planar robots.
We implemented such decomposed predicates in our open-source Core Library. The experiments show that our algorithms are effective, perform in real time on non-trivial environments, and can outperform many sampling-based methods
Malay Lexicon Projects
No full textThe Malay Lexicon Projects represent a series of developments of a Malay word corpus from 2021 - 2025.
MLP (Yap, Liow, Jalil, & Faizal, 2010) contains lexical information, MLP2 (Maziyah Mohamed, Yap, Chee, & Jared, 2023) contains morphological information, and MLP3 contains semantic information (Maziyah Mohamed & Jared, 2025). The MLP3 is a work in progress
Path Planning for Simple Robots using Soft Subdivision Search
No full textThe concept of resolution-exact path planning is a theoretically sound alternative to the standard exact algorithms, and provides much stronger guarantees than probabilistic or sampling algorithms. It opens the way for the introduction of soft predicates in the context of subdivision algorithm. Taking a leaf from the great success of the Probabilistic Road Map (PRM) framework, we formulate an analogous framework for subdivision, called Soft Subdivision Search (SSS). In this video, we illustrate the SSS framework for a trio of simple planar robots: disc, triangle and 2-links. These robots have, respectively, 2, 3 and 4 degrees of freedom. Our 2-link robot can also avoid self-crossing. These algorithms operate in realtime and are relatively easy to implement
Rods and Rings: Soft Subdivision Planner for R^3 x S^2
No full textWe consider path planning for a rigid spatial robot moving amidst polyhedral obstacles. Our robot is either a rod or a ring. Being axially-symmetric, their configuration space is R^3 x S^2 with 5 degrees of freedom (DOF). Correct, complete and practical path planning for such robots is a long standing challenge in robotics. While the rod is one of the most widely studied spatial robots in path planning, the ring seems to be new, and a rare example of a non-simply-connected robot. This work provides rigorous and complete algorithms for these robots with theoretical guarantees. We implemented the algorithms in our open-source Core Library. Experiments show that they are practical, achieving near real-time performance. We compared our planner to state-of-the-art sampling planners in OMPL [Sucan et al., 2012].
Our subdivision path planner is based on the twin foundations of epsilon-exactness and soft predicates. Correct implementation is relatively easy. The technical innovations include subdivision atlases for S^2, introduction of Sigma_2 representations for footprints, and extensions of our feature-based technique for "opening up the blackbox of collision detection"
Isotopic arrangement of simple curves:An exact numerical approach based on subdivision
No full textWe present a purely numerical (i.e., non-algebraic) subdivision algorithm for computing an isotopic approximation of a simple arrangement of curves. The arrangement is "simple" in the sense that any three curves have no common intersection, any two curves intersect transversally, and each curve is non-singular. A curve is given as the zero set of an analytic function on the plane, along with effective interval forms of the function and its partial derivatives. Our solution generalizes the isotopic curve approximation algorithms of Plantinga-Vegter (2004) and Lin-Yap (2009). We use certified numerical primitives based on interval methods. Such algorithms have many favorable properties: they are practical, easy to implement, suffer no implementation gaps, integrate topological with geometric computation, and have adaptive as well as local complexity. A preliminary implementation is available in Core Library.</p
Human health risks of heavy metals via consumption of Musa paradisiaca and the ecological risk assessment of heavy metals in the habitat topsoils
No full textBanana Musa paradisiaca collected from three sites in Peninsular Malaysia were determined for human health risk assessment of Cu, Fe, Ni, Pb and Zn. The metal distribution in the different parts of bananas and their habitat topsoils were in the following orders; Cu: Flesh > peel ≥ root > soil ≥ leaf > stem. Fe: Soil > root > stem > leaf > flesh > peel; Ni: Leave ≥ stem ≥ peel > flesh > root ≥ soil; Zn: Root > soil ≥ leaf ≥ flesh > stem ≥ peel; Pb: Root > soil > stem > leave > flesh ≥ peel. The metal concentrations (mg/kg dry weight) in the banana flesh were 13.87-16.43 for Cu, 29.80-54.47 for Fe, 1.57 13.10 for Ni, 1.70-6.40 for Pb, and 7.03-22.27 for Zn. The target hazard quotient values of all metals were found below 1.0, indicating that average and high level consumers would not have non-carcinogenic risk due to the intake of heavy metals via banana consumption. The potential ecological risk index of the habitat topsoils for all three sites were also categorized as ‘low ecological risk.
Certified Approximation Algorithms for the Fermat Point and n-Ellipses
No full textGiven a set A of n points in ℝ^d with weight function w: A→ℝ_{> 0}, the Fermat distance function is φ(x): = ∑_{a∈A}w(a)‖x-a‖. A classic problem in facility location dating back to 1643, is to find the Fermat point x*, the point that minimizes the function φ. We consider the problem of computing a point x̃* that is an ε-approximation of x* in the sense that ‖x̃*-x*‖ φ(x*) and d = 2. Finally, all our planar (d = 2) algorithms are implemented in order to experimentally evaluate them, using both synthetic as well as real world datasets. These experiments show the practicality of our techniques
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