The integration of phase-contrast magnetic resonance images (PC-MRI) and computational fluid dynamics (CFD) is a way to obtain detailed information of patient-specific hemodynamics. This study proposes a novel strategy for imposing a pressure condition on the outlet boundary (called the outlet pressure) in CFD to minimize velocity differences between the PC-MRI measurement and the CFD simulation, and to investigate the effects of outlet pressure on the numerical solution. The investigation involved ten patient-specific aneurysms reconstructed from a digital subtraction angiography image, specifically on aneurysms located at the bifurcation region. To evaluate the effects of imposing the outlet pressure, three different approaches were used, namely: a pressure-fixed (P-fixed) approach; a flow rate control (Q-control) approach; and a velocity-field-optimized (V-optimized) approach. Numerical investigations show that the highest reduction in velocity difference always occurs in the V-optimized approach, where the mean of velocity difference (normalized by inlet velocity) is 19.3%. Additionally, the highest velocity differences appear near to the wall and vessel bifurcation for 60% of the patients, resulting in differences in wall shear stress. These findings provide a new methodology for PC-MRI integrated CFD simulation and are useful for understanding the evaluation of velocity difference between the PC-MRI and CFD.

This paper presents a novel data assimilation method for patient-specific blood flow analysis based on feedback control theory called the physically consistent feedback control-based data assimilation (PFC-DA) method. In the PFC-DA method, the signal, which is the residual error term of the velocity when comparing the numerical and reference measurement data, is cast as a source term in a Poisson equation for the scalar potential field that induces flow in a closed system. The pressure values at the inlet and outlet boundaries are recursively calculated by this scalar potential field. Hence, the flow field is physically consistent because it is driven by the calculated inlet and outlet pressures, without any artificial body forces. As compared with existing variational approaches, although this PFC-DA method does not guarantee the optimal solution, only one additional Poisson equation for the scalar potential field is required, providing a remarkable improvement for such a small additional computational cost at every iteration. Through numerical examples for 2D and 3D exact flow fields, with both noise-free and noisy reference data as well as a blood flow analysis on a cerebral aneurysm using actual patient data, the robustness and accuracy of this approach is shown. Moreover, the feasibility of a patient-specific practical blood flow analysis is demonstrated.

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The study investigates and develops components for implementing an effective and efficient military knowledge/information/communication in closed network architecture. Since military personnel are always on the move, the dissemination of knowledge/information/communication needs a mobile platform to accommodate mobility of people. The mobile and wireless network platform should be able to sustain the remoteness and seclusion of military operation areas. Communication is one of key problems of a military operation especially due to environmental constraints. This study proposes on establishing a future soldier communication device with mobile wireless sensor network (WSN) and mobile network to suit the infantry operations in the jungle. The operational areas are considered to restricted and challenging locations. Wireless sensor network (WSN) will become inexpensive and common over the next decade Thus, a thorough study is vital to develop the most suitable smart equipment and network requirements for Malaysia’s military eco-system. Finally, this study has successfully developed new smart device prototype using WSN approach for Military operation. In addition, this prototype can be used for Search and Rescue (SAR) operation. This prototype is able to transmit death and location status, movement location status, health monitoring and status to the base station.

In Malaysia, cervical cancer is the top three most common cancer among women. Vaccination and screening are mandatory for the prevention of the disease. Therefore, we aimed to develop a serious game for Malaysian adolescents, the "HPV Vaccine” game objectively to transmit knowledge about human papillomavirus (HPV), create awareness of cervical cancer, and promote HPV vaccine uptake. This game development targeted teenagers aged 10 to 17 years. We expect to complete three levels and answer all 15 questions. Inclusion criteria were Malaysian citizens, who owned a computer with connectivity to the game. We excluded those with a physical disability. This game was the first edutainment on Human papillomavirus, cervical cancer, and the HPV vaccine. We conducted a preliminary study, cross-sectionally, purposive sampling method. We recruited 20 participants; only 16 participants consented and completed the study. All participants enjoyed the wireframes of the game, with an average of 12 to 15 minutes to complete the game. Results demonstrate that participants were highly engaged with the “HPV Vaccine” game. We believe this game, is a forward technology that will beneficial for adolescents' adherence to HPV vaccination. In the future, we suggest an observational study to assess players' perspectives on this game.

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The recent diagnostic assessment of cerebrovascular disease makes use of computational fluid dynamics (CFD) to quantify blood flow and determine the hemodynamics factors contributing to the disease from patient-specific models. However, compliant and anatomical patient-specific geometries are generally reconstructed from the medical images with different threshold values subjectively. Therefore, this paper tends to present the effect of extracted geometry with different threshold coefficient, Cthres by using a patient-specific cerebral aneurysm model. A set of medical images, digital subtraction angiography (DSA) images from the real patient diagnosed with internal carotid artery (ICA) aneurysm was obtained. The threshold value used to extract the patient-specific cerebral aneurysm geometry was calculated by using a simple threshold determination method. Several threshold coefficients, Cthres such as 0.2, 0.3, 0.4, 0.5 and 0.6 were employed in the image segmentation creating three-dimensional (3D) realistic arterial geometries that were then used for CFD simulation. As a result, we obtained that the volume of patient-specific cerebral aneurysm geometry decreases as the threshold coefficient, Cthres increases. There is dislocation of artery attached to the ICA aneurysm geometry occurred at a high threshold coefficient, Cthres. Besides, the physical changes also bring remarkable physiological effect on the wall shear stress (WSS) distribution and velocity flow field at patient-specific cerebral aneurysm geometry reconstructed with different threshold coefficient, Cthres.

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