9 research outputs found
A genetic programming based fuzzy regression approach to modelling manufacturing processes
Fuzzy regression has demonstrated its ability to model manufacturing processes in which the processes have fuzziness and the number of experimental data sets for modelling them is limited. However, previous studies only yield fuzzy linear regression based process models in which variables or higher order terms are not addressed. In fact, it is widely recognised that behaviours of manufacturing processes do often carry interactions among variables or higher order terms. In this paper, a genetic programming based fuzzy regression GP-FR, is proposed for modelling manufacturing processes. The proposed method uses the general outcome of GP to construct models the structure of which is based on a tree representation, which could carry interaction and higher order terms. Then, a fuzzy linear regression algorithm is used to estimate the contributions and the fuzziness of each branch of the tree, so as to determine the fuzzy parameters of the genetic programming based fuzzy regression model.To evaluate the effectiveness of the proposed method for process modelling, it was applied to the modelling of a solder paste dispensing process. Results were compared with those based on statistical regression and fuzzy linear regression. It was found that the proposed method can achieve better goodness-of-fitness than the other two methods. Also the prediction accuracy of the model developed based on GP-FR is better than those based on the other two methods
Surgical outcomes of robotic-assisted laparoscopic radical prostatectomy (RALRP) on Chinese prostate cancer patients: five-year experience from a single tertiary center in Hong Kong
Poster Presentation (Abstract)This free journal suppl. entitled: Special Issue: RCSEd/CSHK Conjoint Scientific Congress 2016, Making Wise Choices in Surgery, 17–18 September 2016, Aberdeen, Hong KongAIM: To assess surgical outcome of RaLRP performed by a single consultant urologist in our centre; in addition to identify factors affecting operative outcomes. METHODS: We reviewed our prospectively-collected data of RaLRP performed on Chinese patients between September 2011 and October 2015. Patients with previous radiotherapy were excluded. Outcomes studied included: rate of positive surgical margin, post-operative complications, 12-month continence rate, and 12-month success of vaginal penetration …link_to_OA_fulltex
Variability of the prevalence of undiagnosed airflow obstruction in smokers using different diagnostic criteria
Variability of the prevalence of undiagnosed airflow obstruction in smokers using different diagnostic criteria
Purpose: To estimate the prevalence of undiagnosed airflow obstruction (AFO) in Hong Kong smokers with no previous diagnosis of respiratory disease, and to assess its variability when applying different prediction equations and diagnostic criteria. Methods: A multicenter, population-based, cross-sectional prevalence study was performed in smokers aged 20 to 80 years. Three different criteria (fixed 70% [Global Initiative for Chronic Obstructive Lung Disease and British Thoracic Society], fixed 75%, and European Respiratory Society [ERS]) were applied to define a lower limit of normal (LLN) of the FEV 1/FVC ratio to compare with the Hong Kong Chinese reference equation (criterion 1), which had used a distribution-free method to obtain the lower fifth percentile of FEV 1/FVC ratio as the LLN. Results: In 525 male patients, using criterion 1 (local internal prediction equation) and defining AFO as FEV 1/FVC less than LLN, the overall prevalence of AFO was 13.7%: 8.3% in age ≥ 20 to 40 years, 14.0% in age ≥ 40 to 60 years, and 17.8% in age ≥ 60 to 80 years. When the local internal prediction equation was used as the comparison reference, the fixed-ratio methods tended to miss AFO in younger age groups and overdiagnose AFO in old age, while the ERS criteria, which uses an almost lower fifth percentile-equivalent method, showed less of such a trend but still only showed moderate agreement with criterion 1. Conclusions: Undiagnosed AFO was prevalent in Hong Kong smokers. Estimated prevalence rates were highly affected by the criteria used to define AFO. The predicted lower fifth percentile values calculated from a local reference equation as the LLN of FEV 1/FVC ratio should be used for the diagnosis of AFO.link_to_subscribed_fulltex
Use of hemostatic matrix to reduce lymphcoceles requiring intervention in renal transplantation: a two center trial
Meeting Theme: Advances in Oncology and EndurologyOral Presentation - Session 8: Update on Urology and Androlog
Floseal hemostatic matrix reduces symptomatic lymphoceles after renal transplantation
Session - Transplantation & Vascular Surgery: Renal Transplantation & Vascular Surgery 1: no. MP29-12This journal suppl. entitled: 2016 Annual Meeting Program Abstracts, AUA Annual MeetingINTRODUCTION AND OBJECTIVES: Lymphoceles are common after kidney transplantation with an incidence ranging from 0.6 to 26%. We evaluate the efficacy of novel use of FloSeal® hemostatic matrix in preventing symptomatic lymphoceles requiring intervention in two renal transplant centers in the territory. METHODS: This was a two-center, matched comparison of cadaveric or living-related renal transplantation performed in patients > 18 years of age between January 2011 and August 2015. Off-label application of FloSeal started since May 2013 in one center and December 2013 in the other. FloSeal (5ml per case) was applied to the graft hilar area and the peri-iliac vessel lymphatic area after graft reperfusion, and then gently compressed for two minutes without any flushing. The incidence of symptomatic lymphoceles were compared in the two groups and evaluated with Kaplan Meier method. Different potential risk factors for lymphocele formation were also reviewed and evaluated with logistic regression analysis. RESULTS: A total of 218 patients (mean age of 44.0 years and mean follow-up of 30.3 months) underwent cadaveric (186) or living-related (32) renal transplant in the period (94 with FloSeal, 124 without FloSeal). There was 8 (8.5%) symptomatic lymphoceles in the FloSeal group compared with 29 (23.4%) in the non-FloSeal group (p=0.004). Duration of renal replacement therapy and duration of peritoneal dialysis were also significantly associated with symptomatic lymphoceles in univariate analysis for risk factor analysis, but upon multivariate analysis using logistic regression, FloSeal use was the only independent factor (OR = 0.31 [CI 0.13-0.73], p = 0.007) for symptomatic lymphoceles. Symptomatic lymphoceles in FloSeal group presented and were intervened significantly earlier than in non-FloSeal group. No adverse events associated with FloSeal use were reported. CONCLUSIONS: Our data suggest that the use of FloSeal can reduce symptomatic lymphoceles in renal transplantation. Further cost analysis is useful in evaluating its cost-effectiveness in lymphocele treatment
The burden of lung disease in Hong Kong: A report from the Hong Kong Thoracic Society
Background and objective: The burden of lung disease in Hong Kong is not known. This study determined the mortality and hospitalization rates of respiratory diseases in Hong Kong in 2005, their trend in the past decade and their incidence/prevalence. Methods: Mortality data were obtained from the Department of Health and hospitalization data from the Hospital Authority, Hong Kong. Incidence/prevalence data were obtained from local registries or local studies. Trends of mortality and hospitalization rates of various respiratory diseases from 1997 and 2005 were calculated after age standardization and were tested for significance using negative binomial regression analysis. Age standardized mortality rates in Hong Kong were compared with those of the UK and globally. Results: Respiratory disease was the most common cause of mortality and hospitalization in Hong Kong in 2005. Globally and in the UK, cardiovascular disease ranked first in mortality. Respiratory infections ranked first in respiratory mortality, followed by respiratory tract cancer and chronic obstructive lung disease. Respiratory infections also ranked first followed by chronic obstructive lung disease in the utilization of respiratory inpatient bed-days. While mortality rates from all respiratory diseases decreased in the past decade, hospitalization rates remained unchanged. Unlike other respiratory diseases, mortality from respiratory infections have increased since 2001. Smoking is the most important risk factor in non-communicable respiratory diseases. Conclusions: Respiratory disease is responsible for the highest health-care burden locally. Increased efforts in improving management and prevention of these diseases, including tobacco control, improving air quality and vaccination against influenza and pneumococci, are necessary. © 2008 The Authors.link_to_subscribed_fulltex