MyMedR

Displaying publications 1 - 20 of 28 in total

Abstract:

Sort:

General form of domination polynomial for two types of graphs associated to dihedral groups

Nabilah Najmuddin, Nor Haniza Sarmin, Ahmad Erfanian

MATEMATIKA, 2019;35(2):149-155.
MyJurnal

A domination polynomial is a type of graph polynomial in which its coefficients represent the number of dominating sets in the graph. There are many researches being done on the domination polynomial of some common types of graphs but not yet for graphs associated to finite groups. Two types of graphs associated to finite groups are the conjugate graph and the conjugacy class graph. A graph of a group G is called a conjugate graph if the vertices are non-central elements of G and two distinct vertices are adjacent if they are conjugate to each other. Meanwhile, a conjugacy class graph of a group G is a graph in which its vertices are the non-central conjugacy classes of G and two distinct vertices are connected if and only if their class cardinalities are not coprime. The conjugate and conjugacy class graph of dihedral groups can be expressed generally as a union of complete graphs on some vertices. In this paper, the domination polynomials are computed for the conjugate and conjugacy class graphs of the dihedral groups.

Matched MeSH terms: Computer Graphics
Orderings a class of unicyclic graphs with respect to Hosoya dan Merrifield-Simmons index

Wang Yan-feng, Ma Ning

Sains Malaysiana, 2016;45:55-58.

Hosoya and Merrifield-Simmons index were the two valuable topological indices in chemical graph theory. The Hosoya and Merrifield-Simmons index of the class of unicyclic graphs G(k) were investigated, according to the distance between u and v on Cm, their orderings with respect to these two topological indices were obtained.

Matched MeSH terms: Computer Graphics
Fulltext Local convexity-preserving C2 rational cubic spline for convex data

Abbas M, Abd Majid A, Ali JM

ScientificWorldJournal, 2014;2014:391568.
PMID: 24757421 DOI: 10.1155/2014/391568

We present the smooth and visually pleasant display of 2D data when it is convex, which is contribution towards the improvements over existing methods. This improvement can be used to get the more accurate results. An attempt has been made in order to develop the local convexity-preserving interpolant for convex data using C(2) rational cubic spline. It involves three families of shape parameters in its representation. Data dependent sufficient constraints are imposed on single shape parameter to conserve the inherited shape feature of data. Remaining two of these shape parameters are used for the modification of convex curve to get a visually pleasing curve according to industrial demand. The scheme is tested through several numerical examples, showing that the scheme is local, computationally economical, and visually pleasing.

Matched MeSH terms: Computer Graphics*
Fulltext Preventing shoulder-surfing attack with the concept of concealing the password objects' information

Ho PF, Kam YH, Wee MC, Chong YN, Por LY

ScientificWorldJournal, 2014;2014:838623.
PMID: 24991649 DOI: 10.1155/2014/838623

Traditionally, picture-based password systems employ password objects (pictures/icons/symbols) as input during an authentication session, thus making them vulnerable to "shoulder-surfing" attack because the visual interface by function is easily observed by others. Recent software-based approaches attempt to minimize this threat by requiring users to enter their passwords indirectly by performing certain mental tasks to derive the indirect password, thus concealing the user's actual password. However, weaknesses in the positioning of distracter and password objects introduce usability and security issues. In this paper, a new method, which conceals information about the password objects as much as possible, is proposed. Besides concealing the password objects and the number of password objects, the proposed method allows both password and distracter objects to be used as the challenge set's input. The correctly entered password appears to be random and can only be derived with the knowledge of the full set of password objects. Therefore, it would be difficult for a shoulder-surfing adversary to identify the user's actual password. Simulation results indicate that the correct input object and its location are random for each challenge set, thus preventing frequency of occurrence analysis attack. User study results show that the proposed method is able to prevent shoulder-surfing attack.

Matched MeSH terms: Computer Graphics/standards*
A low-cost, high-quality method for remote recording of presentations

Tan LK, Wong JH, Ng KH

AJR Am J Roentgenol, 2006 Mar;186(3):898-901.
PMID: 16498128

The purpose of this article was to develop a low-cost method for high-quality remote capturing and recording of multimedia presentations.

Matched MeSH terms: Computer Graphics*
A New Framework for Analysis of Coevolutionary Systems-Directed Graph Representation and Random Walks

Chong SY, Tiňo P, He J, Yao X

Evol Comput, 2019;27(2):195-228.
PMID: 29155606 DOI: 10.1162/evco_a_00218

Studying coevolutionary systems in the context of simplified models (i.e., games with pairwise interactions between coevolving solutions modeled as self plays) remains an open challenge since the rich underlying structures associated with pairwise-comparison-based fitness measures are often not taken fully into account. Although cyclic dynamics have been demonstrated in several contexts (such as intransitivity in coevolutionary problems), there is no complete characterization of cycle structures and their effects on coevolutionary search. We develop a new framework to address this issue. At the core of our approach is the directed graph (digraph) representation of coevolutionary problems that fully captures structures in the relations between candidate solutions. Coevolutionary processes are modeled as a specific type of Markov chains-random walks on digraphs. Using this framework, we show that coevolutionary problems admit a qualitative characterization: a coevolutionary problem is either solvable (there is a subset of solutions that dominates the remaining candidate solutions) or not. This has an implication on coevolutionary search. We further develop our framework that provides the means to construct quantitative tools for analysis of coevolutionary processes and demonstrate their applications through case studies. We show that coevolution of solvable problems corresponds to an absorbing Markov chain for which we can compute the expected hitting time of the absorbing class. Otherwise, coevolution will cycle indefinitely and the quantity of interest will be the limiting invariant distribution of the Markov chain. We also provide an index for characterizing complexity in coevolutionary problems and show how they can be generated in a controlled manner.

Matched MeSH terms: Computer Graphics*
Fulltext Computers in health education

Krishnan R, Kueh ST, Lin YM, Samsuri MF, Seng OC, Mahadavan M, et al.

World Health Forum, 1990;11(3):310-1.
PMID: 2291796
Matched MeSH terms: Computer Graphics*
Fulltext Soft bilateral filtering volumetric shadows using cube shadow maps

Ali HH, Sunar MS, Kolivand H

PLoS One, 2017;12(6):e0178415.
PMID: 28632740 DOI: 10.1371/journal.pone.0178415

Volumetric shadows often increase the realism of rendered scenes in computer graphics. Typical volumetric shadows techniques do not provide a smooth transition effect in real-time with conservation on crispness of boundaries. This research presents a new technique for generating high quality volumetric shadows by sampling and interpolation. Contrary to conventional ray marching method, which requires extensive time, this proposed technique adopts downsampling in calculating ray marching. Furthermore, light scattering is computed in High Dynamic Range buffer to generate tone mapping. The bilateral interpolation is used along a view rays to smooth transition of volumetric shadows with respect to preserving-edges. In addition, this technique applied a cube shadow map to create multiple shadows. The contribution of this technique isreducing the number of sample points in evaluating light scattering and then introducing bilateral interpolation to improve volumetric shadows. This contribution is done by removing the inherent deficiencies significantly in shadow maps. This technique allows obtaining soft marvelous volumetric shadows, having a good performance and high quality, which show its potential for interactive applications.

Matched MeSH terms: Computer Graphics*
Fulltext Generalized and improved (G'/G)-expansion method for (3+1)-dimensional modified KdV-Zakharov-Kuznetsev equation

Naher H, Abdullah FA, Akbar MA

PLoS One, 2013;8(5):e64618.
PMID: 23741355 DOI: 10.1371/journal.pone.0064618

The generalized and improved (G'/G)-expansion method is a powerful and advantageous mathematical tool for establishing abundant new traveling wave solutions of nonlinear partial differential equations. In this article, we investigate the higher dimensional nonlinear evolution equation, namely, the (3+1)-dimensional modified KdV-Zakharov-Kuznetsev equation via this powerful method. The solutions are found in hyperbolic, trigonometric and rational function form involving more parameters and some of our constructed solutions are identical with results obtained by other authors if certain parameters take special values and some are new. The numerical results described in the figures were obtained with the aid of commercial software Maple.

Matched MeSH terms: Computer Graphics
Fulltext The effectiveness of interactive learning in manufacturing engineering

Nadia Abdul Rani, Faieza Abdul Aziz, Rohidatun M,W.

Journal of Engineering and Science Research, 2018;2(6):10-16.
MyJurnal

Interactive learning is a pedagogical model that encourages students to be part of the lesson instead of passive observers, quietly sitting at a desk taking notes or memorizing information. Students interact with the material, each other and the teacher in an active way. The new emerging technologies that can overcome some of the potential difficulties in this area includes computer graphics, augmented reality, computational dynamics, and virtual worlds. Therefore, the manufacturing industry relies on new design concepts and methods undertake the challenges in integrating technologies to expedite the march towards industrial revolution 4.0.This paper reviews and investigates the current context of the use of interactive learning such as Virtual Reality(VR),Augmented Reality(AR),Computer aided design and manufacturing(CADCAM), computer graphics, computational dynamics and new emerging technologies that effect on students and lectures in learning and teaching environments for Manufacturing Engineering. Interactive learning is part of the factors that could influence the self-learning and regulations environments.

Matched MeSH terms: Computer Graphics
Fulltext Graphery: interactive tutorials for biological network algorithms

Zeng H, Zhang J, Preising GA, Rubel T, Singh P, Ritz A

Nucleic Acids Res, 2021 07 02;49(W1):W257-W262.
PMID: 34037782 DOI: 10.1093/nar/gkab420

Networks have been an excellent framework for modeling complex biological information, but the methodological details of network-based tools are often described for a technical audience. We have developed Graphery, an interactive tutorial webserver that illustrates foundational graph concepts frequently used in network-based methods. Each tutorial describes a graph concept along with executable Python code that can be interactively run on a graph. Users navigate each tutorial using their choice of real-world biological networks that highlight the diverse applications of network algorithms. Graphery also allows users to modify the code within each tutorial or write new programs, which all can be executed without requiring an account. Graphery accepts ideas for new tutorials and datasets that will be shaped by both computational and biological researchers, growing into a community-contributed learning platform. Graphery is available at https://graphery.reedcompbio.org/.

Matched MeSH terms: Computer Graphics
Mechanism diagrams and abstraction-by-aggregation

Tee SH

Stud Hist Philos Biol Biomed Sci, 2018 Oct;71:17-25.
PMID: 30318277 DOI: 10.1016/j.shpsc.2018.10.003

Mechanism diagrams exhibit visually the organized parts and operations of a biological mechanism. A mechanism diagram can facilitate mechanistic research by providing a mechanistic explanation of the phenomenon of interest. Much research has been focusing on the mechanistic explanation and the explanatory mechanistic models. As a specific type of scientific diagram, a simple mechanism diagram can be explanatory by drawing on the rich explanatory resources of non-depicted background knowledge. The relationship between the visually depicted and the background knowledge is underexplored. It is unclear how the non-depicted background knowledge of a mechanism diagram contributes to providing a better-informed explanation of the phenomenon of interest in biological sciences. With the aim to explore this relationship, I articulate that a mechanism diagram provides a mechanistic explanation by a process called abstraction-by-aggregation. Through visual cues, the unified relevant background knowledge provides an epistemic access to a better-informed explanation.

Matched MeSH terms: Computer Graphics
Fulltext Design and development of a spatial immersive track cycling simulator

Yap, H.J., Tan, C.H., Sivadas, C.S., Wan, W.L., Taha, Z., Chang, S.W.

Movement Health & Exercise, 2018;7(2):39-52.
MyJurnal

Virtual Reality (VR) is a technology that makes use of computer graphics,
algorithms and special hardware to simulate the real world in real time. There
are four main elements required to make a VR system a success, namely
virtual world, immersion, sensory feedback and interactivity. The virtual
world created must be as real as possible. Users should have a sense of
immersion in the virtual world. Position tracking is usually incorporated into
a VR system for visual, sound and force feedback on the users and the virtual
objects in the VR world must be interact-able with the users. VR has proven
to be effective in training and widely used in many areas, for example medical
surgery, dental treatment, psychology treatment for phobia, engineering
design, maintenance and repair, sports and many more. By implementing VR
technology in training, users are able to reduce the training cost and time. VR
training is also safer for users, as harsh environments can be simulated despite
the environment and/or human factors. On the other hand, the physical
facilities and infrastructures of the track cycling are very costly. In track
cycling, the game field, known as a velodrome, requires a large space of area.
It requires a huge budget and professional manpower to maintain these
facilities. Therefore, the proposed spatial immersive track cycling simulator
is invented to overcome these issues. The aim of this study is to simulate the
velodrome track cycling in VR environment and synchronize with a 6 degreeof-freedom
motion platform. The simulator is aimed to be low cost and
minimal space requirement compared to actual velodrome. A trainee who
undergoes VR track cycling simulator training wears a head-mounted-display (HMD) to visualize the VR environment. An actual bike will be mounted on
the 6-DOF motion platform, which the platform will synchronize with the VR
environment to simulate the track condition for the training purposes. An
encoder is placed at the bicycle wheel to feedback the moving speed and
synchronize the visualize feedback to the HMD.

Matched MeSH terms: Computer Graphics
The Suffering Pictogram: Measuring Suffering in Palliative Care

Beng TS, Ann YH, Guan NC, Chin LE, Loong LC, Ying NT, et al.

J Palliat Med, 2017 08;20(8):869-874.
PMID: 28410449 DOI: 10.1089/jpm.2016.0448

BACKGROUND: Measuring suffering objectively presents a challenge because suffering is a unique and subjective experience. However, objective tools are of profound importance in the detection and management of suffering in clinical practice for optimal patient care.
OBJECTIVE: The objective of the study is to assess the psychometric properties of the Suffering Pictogram, a new suffering assessment instrument on a population of palliative care patients.
DESIGN AND SETTING: This is a validation study conducted at University of Malaya Medical Centre, Kuala Lumpur, Malaysia. Ninety one palliative care patients were recruited. Patients were interviewed with the Suffering Pictogram and FACIT-Sp.
RESULTS: The median completion time for the Suffering Pictogram was five minutes. The Suffering Pictogram showed good internal consistency, with a Cronbach's alpha of 0.836. The total scores of the Suffering Pictogram correlated strongly and negatively with FACIT-Sp total score (Spearman's Rho = -0.625, p

Matched MeSH terms: Computer Graphics*
Fulltext A Method for Quantifying, Visualising, and Analysing Gastropod Shell Form

Liew TS, Schilthuizen M

PLoS One, 2016;11(6):e0157069.
PMID: 27280463 DOI: 10.1371/journal.pone.0157069

Quantitative analysis of organismal form is an important component for almost every branch of biology. Although generally considered an easily-measurable structure, the quantification of gastropod shell form is still a challenge because many shells lack homologous structures and have a spiral form that is difficult to capture with linear measurements. In view of this, we adopt the idea of theoretical modelling of shell form, in which the shell form is the product of aperture ontogeny profiles in terms of aperture growth trajectory that is quantified as curvature and torsion, and of aperture form that is represented by size and shape. We develop a workflow for the analysis of shell forms based on the aperture ontogeny profile, starting from the procedure of data preparation (retopologising the shell model), via data acquisition (calculation of aperture growth trajectory, aperture form and ontogeny axis), and data presentation (qualitative comparison between shell forms) and ending with data analysis (quantitative comparison between shell forms). We evaluate our methods on representative shells of the genera Opisthostoma and Plectostoma, which exhibit great variability in shell form. The outcome suggests that our method is a robust, reproducible, and versatile approach for the analysis of shell form. Finally, we propose several potential applications of our methods in functional morphology, theoretical modelling, taxonomy, and evolutionary biology.

Matched MeSH terms: Computer Graphics*
Fulltext Intelligent bar chart plagiarism detection in documents

Al-Dabbagh MM, Salim N, Rehman A, Alkawaz MH, Saba T, Al-Rodhaan M, et al.

ScientificWorldJournal, 2014;2014:612787.
PMID: 25309952 DOI: 10.1155/2014/612787

This paper presents a novel features mining approach from documents that could not be mined via optical character recognition (OCR). By identifying the intimate relationship between the text and graphical components, the proposed technique pulls out the Start, End, and Exact values for each bar. Furthermore, the word 2-gram and Euclidean distance methods are used to accurately detect and determine plagiarism in bar charts.

Matched MeSH terms: Computer Graphics
Fulltext A novel state space reduction algorithm for team formation in social networks

Rehman MZ, Zamli KZ, Almutairi M, Chiroma H, Aamir M, Kader MA, et al.

PLoS One, 2021;16(12):e0259786.
PMID: 34855771 DOI: 10.1371/journal.pone.0259786

Team formation (TF) in social networks exploits graphs (i.e., vertices = experts and edges = skills) to represent a possible collaboration between the experts. These networks lead us towards building cost-effective research teams irrespective of the geolocation of the experts and the size of the dataset. Previously, large datasets were not closely inspected for the large-scale distributions & relationships among the researchers, resulting in the algorithms failing to scale well on the data. Therefore, this paper presents a novel TF algorithm for expert team formation called SSR-TF based on two metrics; communication cost and graph reduction, that will become a basis for future TF's. In SSR-TF, communication cost finds the possibility of collaboration between researchers. The graph reduction scales the large data to only appropriate skills and the experts, resulting in real-time extraction of experts for collaboration. This approach is tested on five organic and benchmark datasets, i.e., UMP, DBLP, ACM, IMDB, and Bibsonomy. The SSR-TF algorithm is able to build cost-effective teams with the most appropriate experts-resulting in the formation of more communicative teams with high expertise levels.

Matched MeSH terms: Computer Graphics
Multiresolution wavelet analysis for efficient analysis, compression and remote display of long-term physiological signals

Khuan LY, Bister M, Blanchfield P, Salleh YM, Ali RA, Chan TH

Australas Phys Eng Sci Med, 2006 Jun;29(2):216-28.
PMID: 16845928

Increased inter-equipment connectivity coupled with advances in Web technology allows ever escalating amounts of physiological data to be produced, far too much to be displayed adequately on a single computer screen. The consequence is that large quantities of insignificant data will be transmitted and reviewed. This carries an increased risk of overlooking vitally important transients. This paper describes a technique to provide an integrated solution based on a single algorithm for the efficient analysis, compression and remote display of long-term physiological signals with infrequent short duration, yet vital events, to effect a reduction in data transmission and display cluttering and to facilitate reliable data interpretation. The algorithm analyses data at the server end and flags significant events. It produces a compressed version of the signal at a lower resolution that can be satisfactorily viewed in a single screen width. This reduced set of data is initially transmitted together with a set of 'flags' indicating where significant events occur. Subsequent transmissions need only involve transmission of flagged data segments of interest at the required resolution. Efficient processing and code protection with decomposition alone is novel. The fixed transmission length method ensures clutter-less display, irrespective of the data length. The flagging of annotated events in arterial oxygen saturation, electroencephalogram and electrocardiogram illustrates the generic property of the algorithm. Data reduction of 87% to 99% and improved displays are demonstrated.

Matched MeSH terms: Computer Graphics*
Fulltext Realistic real-time outdoor rendering in augmented reality

Kolivand H, Sunar MS

PLoS One, 2014;9(9):e108334.
PMID: 25268480 DOI: 10.1371/journal.pone.0108334

Realistic rendering techniques of outdoor Augmented Reality (AR) has been an attractive topic since the last two decades considering the sizeable amount of publications in computer graphics. Realistic virtual objects in outdoor rendering AR systems require sophisticated effects such as: shadows, daylight and interactions between sky colours and virtual as well as real objects. A few realistic rendering techniques have been designed to overcome this obstacle, most of which are related to non real-time rendering. However, the problem still remains, especially in outdoor rendering. This paper proposed a much newer, unique technique to achieve realistic real-time outdoor rendering, while taking into account the interaction between sky colours and objects in AR systems with respect to shadows in any specific location, date and time. This approach involves three main phases, which cover different outdoor AR rendering requirements. Firstly, sky colour was generated with respect to the position of the sun. Second step involves the shadow generation algorithm, Z-Partitioning: Gaussian and Fog Shadow Maps (Z-GaF Shadow Maps). Lastly, a technique to integrate sky colours and shadows through its effects on virtual objects in the AR system, is introduced. The experimental results reveal that the proposed technique has significantly improved the realism of real-time outdoor AR rendering, thus solving the problem of realistic AR systems.

Matched MeSH terms: Computer Graphics
Determining level of postural control in young adults using force-sensing resistors

Gopalai AA, Senanayake SM, Gouwanda D

IEEE Trans Inf Technol Biomed, 2011 Jul;15(4):608-14.
PMID: 21478080 DOI: 10.1109/TITB.2011.2140378

A force-sensing platform (FSP), sensitive to changes of the postural control system was designed. The platform measured effects of postural perturbations in static and dynamic conditions. This paper describes the implementation of an FSP using force-sensing resistors as sensing elements. Real-time qualitative assessment utilized a rainbow color scale to identify areas with high force concentration. Postprocessing of the logged data provided end-users with quantitative measures of postural control. The objective of this research was to establish the feasibility of using an FSP to test and gauge human postural control. Tests were conducted in eye open and eye close states. Readings obtained were tested for repeatability using a one-way analysis of variance test. The platform gauged postural sway by measuring the area of distribution for the weighted center of applied pressure at the foot. A fuzzy clustering algorithm was applied to identify regions of the foot with repetitive pressure concentration. Potential application of the platform in a clinical setting includes monitoring rehabilitation progress of stability dysfunction. The platform functions as a qualitative tool for initial, on-the-spot assessment, and quantitative measure for postacquisition assessment on balance abilities.

Matched MeSH terms: Computer Graphics

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links