Multi-fidelity uncertainty quantification of high Reynolds number turbulent flow around a rectangular 5:1 Cylinder

Mayu Sakuma,Nick Pepper,Suneth Warnakulasuriya,Francesco Montomoli,Roland Wüchner,Kai-Uwe Bletzinger 한국풍공학회 2022 Wind and Structures, An International Journal (WAS Vol.34 No.1

In this work a multi-fidelity non-intrusive polynomial chaos (MF-NIPC) has been applied to a structural wind engineering problem in architectural design for the first time. In architectural design it is important to design structures that are safe in a range of wind directions and speeds. For this reason, the computational models used to design buildings and bridges must account for the uncertainties associated with the interaction between the structure and wind. In order to use the numerical simulations for the design, the numerical models must be validated by experi-mental data, and uncertainties contained in the experiments should also be taken into account. Uncertainty Quantifi-cation has been increasingly used for CFD simulations to consider such uncertainties. Typically, CFD simulations are computationally expensive, motivating the increased interest in multi-fidelity methods due to their ability to lev-erage limited data sets of high-fidelity data with evaluations of more computationally inexpensive models. Previous-ly, the multi-fidelity framework has been applied to CFD simulations for the purposes of optimization, rather than for the statistical assessment of candidate design. In this paper MF-NIPC method is applied to flow around a rectan-gular 5:1 cylinder, which has been thoroughly investigated for architectural design. The purpose of UQ is validation of numerical simulation results with experimental data, therefore the radius of curvature of the rectangular cylinder corners and the angle of attack are considered to be random variables, which are known to contain uncertainties when wind tunnel tests are carried out. Computational Fluid Dynamics (CFD) simulations are solved by a solver that employs the Finite Element Method (FEM) for two turbulence modeling approaches of the incompressible Navier-Stokes equations: Unsteady Reynolds Averaged Navier Stokes (URANS) and the Large Eddy simulation (LES). The results of the uncertainty analysis with CFD are compared to experimental data in terms of time-averaged pressure coefficients and bulk parameters. In addition, the accuracy and efficiency of the multi-fidelity framework is demonstrated through a comparison with the results of the highfidelity model.

Exophytic Verrucous Hyperplasia of the Oral Cavity - Application of Standardized Criteria for Diagnosis from a Consensus Report

Zain, Rosnah Binti,Kallarakkal, Thomas George,Ramanathan, Anand,Kim, Jin,Tilakaratne, WM,Takata, Takashi,Warnakulasuriya, Saman,Hazarey, Vinay Kumar,Rich, Alison,Hussaini, Haizal Mohd,Jalil, Ajura Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.9

Verruco-papillary lesions (VPLs) of the oral cavity described in the literature involve a spectrum of conditions including squamous papilloma, verruca vulgaris, focal epithelial hyperplasia, condyloma, proliferative verrucous leukoplakia and verrucous carcinoma. A majority of the VPLs are slow growing, benign in nature and have a viral aetiology. Virus associated benign mucosal outgrowths are not too difficult to diagnose either clinically or by microscopy. Apart from virus-associated lesions, VPLs harboring malignant potential or behaviour such as verrucous carcinoma, proliferative verrucous leukoplakia, oral verrucous hyperplasia (OVH), oral papillary squamous cell carcinoma (PSCC) and oral conventional squamous cell carcinoma with papillary features (CSCC) need to be further clarified for better understanding of their predictable biologic behavior and appropriate treatment. Current understanding of potentially malignant VPLs is perplexing and is primarily attributed to the use of confusing and unsatisfactory terminology. In particular, the condition referred to as oral verrucous hyperplasia (OVH) poses a major diagnostic challenge. OVH represents a histopathological entity whose clinical features are not well recognised and is usually clinically indistinguishable from a verrucous carcinoma and a PSCC or a CSCC. A consensus report published by an expert working group from South Asia as an outcome of the 'First Asian Regional Meeting on the Terminology and Criteria for Verruco-papillary Lesions of the Oral Cavity' held in Kuala Lumpur, Malaysia, recognised the clinical description of these OVH as a new entity named 'Exophytic Verrucous Hyperplasia'. Previously described clinical features of OVH such as the 'blunt' or 'sharp' variants; and the 'mass' or 'plaque' variants can now collectively fall under this newly described entity. This paper discusses in detail the application of the standardized criteria guidelines of 'Exophytic Verrucous Hyperplasia' as published by the expert group which will enable clinicians and pathologists to uniformly interpret their pool of OVH cases and facilitate a better understanding of OVH malignant potential.

Relative Frequency of Oral Malignancies and Oral Precancer in the Biopsy Service of Jazan Province, 2009-2014

Idris, AM,Vani, NV,Saleh, Sanna,Tubaigy, Faisal,Alharbi, Fahd,Sharwani, Abubkr,Tadrus, Nabil,Warnakulasuriya, Saman Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.2

Background: The objective of this study was to report the types and relative frequency of oral malignancies and precancer in the Jazan region of Saudi Arabia during the period 2009-2014. Materials and Methods: Pathology reports were retrieved from the archives of Histopathology Department, King Fahd hospital in Jazan. Demographic data on tobacco habits, clinical presentation and histologic grading of oral precancer and cancer cases were transcribed from the files. Results: 303 (42.7%) oral pre-malignant and malignant cases were found out of 714 oral biopsy lesions. A pathology diagnosis of squamous cell carcinoma (85.1%) was most frequent, followed by premalignant lesions/epithelial dysplasia (8.6%), verrucous carcinoma (3.3%) and malignancy of other histological types (3%) such as ameloblastic carcinoma, salivary gland malignancy and sarcomas. Oral squamous cell carcinoma was predominant in females with a male to female ratio of 1:1.9. Patient age ranged from 22 to 100 years with a mean of $65{\pm}13.9$. Almost 44.6% of oral cancer had occurred after 65 years of age. Only 16.3% cases were reported in patients younger than 50 years, predominantly females. The majority of female patients had the habit of using shammah with a long duration of usage for more than 45 years. Buccoalveolar mucosa (52.3%) was the common site of involvement followed by tongue/floor of the mouth (47.7%) and clinically presented mostly as ulceration/swelling clinically. Moderately differentiated tumours (53.9%) were common followed by well differentiated (32.2%) and poorly differentiated tumours (5.8%). The prevalence of oral verrucous carcinoma (3.3%) was comparatively low with an equal distribution in both males and females. Both bucco-alveolar mucosa and tongue were predominantly affected. Oral precancer/epithelial dysplasia (8.6%) was common in females with a shammah habit. Bucco-alveolar mucosa was commonly involved and clinically presented mostly as white/red patches. Most cases were mild followed by moderate and severe dysplasia. Tumours of other histological types (3%) include 1 ameloblastic carcinoma, 3 malignant salivary gland tumours and 5 sarcomas. Conclusions: In this study, it was found that oral cancers reported in the pathology service to be a common occurrence. This study reconfirms previous reports of the high burden of oral cancer in this population This indicates that conventional preventive programs focused on oral cancer are in need of revision. In addition, further research into identifying new risk factors and molecular markers for oral cancer are needed for screening high risk individuals.