Nasopharyngeal examination during transoral upper gastrointestinal endoscopy

Vui Heng Chong 대한소화기내시경학회 2024 Clinical Endoscopy Vol.57 No.1

LETTER TO THE EDITOR

Numerical Study of SF6 arc with Copper Contamination

Vui-Kien Liau,Byeong-Yoon Lee,Ki-Dong Song,Kyong-Yop Park 대한전기학회 2005 KIEE International Transactions on Electrophysics Vol.5C No.6

Investigating Arithmetic Mean, Harmonic Mean, and Average Speed through Dynamic Visual Representations

( Vui Tran ) 한국수학교육학회 2014 수학교육연구 Vol.18 No.1

Working with dynamic visual representations can help students-with-computer discover new mathematical ideas. Students translate among multiple representations as a strategy to investigate non-routine problems to explore possible solutions in mathematics classrooms. In this paper, we use the area models as new representations for our secondary students to investigate three problems related to the average speed of a particle. Students show their ideas in the process of investigating arithmetic mean, harmonic mean, and average speed through their created dynamic figures. These figures really utilize dynamic geometry software.

Increasing Incidence of Colorectal Cancer, Starting at a Younger Age for Rectal Compared to Colon Cancer in Brunei Darussalam

Chong, Vui Heng,Telisinghe, Pemasari Upali,Bickle, Ian,Abdullah, Muhamad Syafiq,Lim, Ediwn,Chong, Chee Fui Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.12

Background: Colorectal cancer (CRC) is the most common gastrointestinal malignancy and is a significant cause of mortality. Its incidence is generally increasing in Asia. Reports from the West have indicated that the incidence of rectal cancer is increasing in the younger population. This study assessed the time trend of CRC in Brunei Darussalam specifically assessing the different age groups at which the incidences start to increase. Materials and Methods: The National Cancer registry was reviewed (1991 to 2014). The age standardized rate (ASR) and the age specific incidence rates (ASIRs) for three time periods (1991-1998), (1999-2006) and (2007-2014) were calculated. Results: The mean age of diagnosis was $59.3{\pm}14.6$ years old, incidences being slightly higher amongst men (57.6%) and Malays (67.1%). The most common tumor type was adenocarcinoma (96.4%). Rectal cancers accounted for 35.2% (n=372/1,056) of all cancers of the large bowel; more men were affected than women. The proportion of rectal cancer was also high among the indigenous group. In the three time periods, the ASR for CRC increased from 16 per 100,000 (1991-1998) to 19.6 per 100,000 (1999-2006) and 24.3 per 100,000 (2007-2014). The ASIRs for CRC increased markedly between the time periods 1998-2006 and 2007-2014, beginning in the 40-44 years age group. For rectal cancers, the ASIRs started to increase in the 25-29 age group onward whereas for colon cancers, the increase was observed at a later age, starting from the 45-49 age group. Conclusions: Our study showed an increase in the incidence of CRC including in the younger age groups. The increase was seen earlier in rectal cancer compared to colon cancer. These data mirror the trends reported from the West.

Poor Knowledge of Colorectal Cancer in Brunei Darussalam

Chong, Vui Heng,Lim, Ai Giok,Baharudin, Hana Naqiyah,Tan, Jackson,Chong, Chee Fui Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.9

Background: Colorectal cancer (CRC) is the most common gastrointestinal cancer and the incidence is increasing in many developing countries. While it can be detected early and even prevented through screening and removal of premalignant lesions, there are barriers to screening which include low level of knowledge and awareness of CRC. This study assessed the level of knowledge of CRC in Brunei Darussalam. Materials and Methods: A total of 431 (262 male and 161 female) subjects participated in this questionnaire study. Subjects were scored on their knowledge of signs/symptoms (maximum 10 correct answers) and known risk factors for CRC (maximum 10 correct answers) and were categorised into poor (0-2), moderate (3-4) and satisfactory (5-10). Comparisons were made between the various patient factors. Results: Overall, 54.1% could not name any CRC signs/symptoms or associated risk factors. Most were not aware of any screening modalities. The overall scores for CRC signs/symptoms and risk factors were $1.3{\pm}1.39$ (range 0-6) and $0.6{\pm}1.05$ (range 0-5) respectively. Overall, the breakdown of scores was: poor (78.1%), moderate (20.3%) and satisfactory (6.2%) for signs/symptoms and poor (93.2%), moderate (6.2%) and satisfactory (0.7%) for risk factors. Higher level of education, female gender and non-Malay race were associated with higher scores for both signs/symptoms and knowledge of screening modality; however the overall scores were low. Conclusions: Our study showed that the general knowledge of CRC in Brunei Darussalam is poor. Being female, with higher levels of education and non-Malay race were associated with higher scores, but they were still generally poor. More needs to be done to increase the public knowledge and awareness of CRC.

Declining Incidence of Nasopharyngeal Carcinoma in Brunei Darussalam: a Three Decade Study (1986-2014)

Chong, Vui Heng,Telisinghe, Pemsari Upali,LIM, Edwin,Abdullah, Muhammad Syafiq,Idris, Fidah,Chong, Chee Fui Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.16

Background: Nasopharyngeal carcinoma (NPC) is linked to Epstein Barr virus infection and is particularly common in the Far East, particularly among some Chinese groups. Certain ethnicities have been reported to have low incidence of NPC. This study looked at NPC in Brunei Darussalam over a three decade period. Materials and Methods: The cancer registry from 1986 to 2014 maintained by the State Laboratory was retrospectively reviewed. The age standardized rates (ASR) and the age specific incidence rates (ASIR) were calculated. Non NPC tumors were excluded from the study. Results: Altogether, there were a total of 450 NPC cases diagnosed accounting for 4.4% of all total cancer cases over the study period, declining from 10.3% in 1986-1990 to 2.3% in 2011-2014. The most common tumor type was the undifferentiated carcinoma (96.4%). The case characteristics were mean age $50.4{\pm}14.4$ years old, male 69%, and predominately Malays 74.4%, followed by Chinese 16.7%. The mean age of diagnosis increased over the study period from $45.6{\pm}17.1$ years (1986-1989) to $54.1{\pm}12.5$ years (ANOVA, p<0.01 for trend). There were no differences in the mean age of diagnosis between the ethnic groups or genders. The ASR showed a declining trend from 11.1 per 100,000 in 1986-1990 to 5.95 per 100,000 in 2011-2014, similar trends been observedfor both genders. Among the age groups, declining trends were seen in all the other age groups apart from the >70 years group. The overall ASRs for the Malays and Chinese were 7.92/100,000 and 8.83/100,000 respectively, both showing declining trends. Conclusions: The incidence of NPC in Brunei Darussalam is comparable to rates reported from Singapore and Malaysia, but higher than rates reported from the other Southeast Asian nations. Unlike higher rates reported for Chinese compared to the Malays in other countries, the rates between the Malays and Chinese in our study was comparable. Importantly, the ASR is declining overall and for both genders and ethnic groups.

Numerical Solution of Nonlinear Diffusion in One Dimensional Porous Medium Using Hybrid SOR Method

Jackel Vui Lung, Chew,Elayaraja, Aruchunan,Andang, Sunarto,Jumat, Sulaiman Department of Mathematics 2022 Kyungpook mathematical journal Vol.62 No.4

This paper proposes a hybrid successive over-relaxation iterative method for the numerical solution of a nonlinear diffusion in a one-dimensional porous medium. The considered mathematical model is discretized using a computational complexity reduction scheme called half-sweep finite differences. The local truncation error and the analysis of the stability of the scheme are discussed. The proposed iterative method, which uses explicit group technique and modified successive over-relaxation, is formulated systematically. This method improves the efficiency of obtaining the solution in terms of total iterations and program elapsed time. The accuracy of the proposed method, which is measured using the magnitude of absolute errors, is promising. Numerical convergence tests of the proposed method are also provided. Some numerical experiments are delivered using initial-boundary value problems to show the superiority of the proposed method against some existing numerical methods.

Emotion recognition from speech using Gammatone auditory filterbank

Ba-Vui Le(레바부이),Young-Koo Lee(이영구),Sungyoung Lee(이승룡) 한국정보과학회 2011 한국정보과학회 학술발표논문집 Vol.38 No.1A

An application of Gammatone auditory filterbank for emotion recognition from speech is described in this paper. Gammatone filterbank is a bank of Gammatone filters which are used as a preprocessing stage before applying feature extraction methods to get the most relevant features for emotion recognition from speech. In the feature extraction step, the energy value of output signal of each filter is computed and combined with other of all filters to produce a feature vector for the learning step. A feature vector is estimated in a short time period of input speech signal to take the advantage of dependence on time domain. Finally, in the learning step, Hidden Markov Model (HMM) is used to create a model for each emotion class and recognize a particular input emotional speech. In the experiment, feature extraction based on Gammatone filterbank (GTF) shows the better outcomes in comparison with features based on Mel-Frequency Cepstral Coefficient (MFCC) which is a well-known feature extraction for speech recognition as well as emotion recognition from speech.

A model for damage analysis of concrete

Cao, Vui V.,Ronagh, Hamid R. Techno-Press 2013 Advances in concrete construction Vol.1 No.2

The damage level in structures (global scale), elements (intermediate scale) and sections (local scale) can be evaluated using a single parameter called the "Damage Index". Part of the damage attributed to the local scale relates to the damage sustained by the materials of which the section is made. This study investigates the damage of concrete subjected to monotonic compressive loading using four different damage models - one proposed here for the first time and three other well-known models. The analytical results show that the proposed model is promising yet simple and effective for evaluating the damage of concrete. The proposed damage model of concrete with its promising characteristics indicated, appears to be a useful tool in the damage assessment of structures made of concrete.

Seismic risk assessment of deficient reinforced concrete frames in near-fault regions

Cao, Vui Van,Ronagh, Hamid Reza,Baji, Hassan Techno-Press 2014 Advances in concrete construction Vol.2 No.4

In many parts of the world, reinforced concrete (RC) buildings, designed and built in accordance with older codes, have suffered severe damage or even collapse as a result of recent near-fault earthquakes. This is particularly due to the deficiencies of most of the older (and even some of the recent) codes in dealing with near fault events. In this study, a tested three-storey frame designed for gravity loads only was selected to represent those deficient buildings. Nonlinear time history analyses were performed, followed by damage assessment procedures. The results were compared with experimental observation of the same frame showing a good match. Damage and fragility analyses of the frame subjected to 204 pulse-type motions were then performed using a selected damage model and inter-storey drifts. The results showed that the frame located in near-fault regions is extremely vulnerable to ground motions. The results also showed that the damage model better captures the damage distribution in the frame than inter-storey drifts. The first storey was identified as the most fragile and the inner columns of the first storey suffered most damage as indicated by the damage index. The findings would be helpful in the decision making process prior to the strengthening of buildings in near-fault regions.