Least square support vector machine (LSSVM) combined with successive projection algorithm (SPA) method was applied for?near-infrared (NIR)?quantitative determination of the octane number in fuel petrol. The NIR spectr...Least square support vector machine (LSSVM) combined with successive projection algorithm (SPA) method was applied for?near-infrared (NIR)?quantitative determination of the octane number in fuel petrol. The NIR spectra of 87 fuel petrol samples were?scanned?for model establishment and optimization. First order derivative Savitzky-Golay smoother?(1st-d’SG) was?utilized to improve the?NIR predictive ability. Its pretreatment effect was compared with the raw data.?SPA was?applied for the extraction of informative wavelengths. Considering the linear and non-linear?training mechanism,?LSSVM?regression was employed to establish calibration models.?The correlation coefficient (R) and root mean square error (RMSE) were used as the model evaluation indices;accordingly the octane number in fuel petrol?was quantitatively determined with the prospective predictive indices. Results showed that?after pretreated by 1st-d’SG, 8 SPA-selected wavelengths?was generated as the inputs of LSSVM, so that the calibration models were optimized in the way of combining the SPA-LSSVM regression with the SG smoother.?The prediction results were quite satisfactory, with the calibrating correlation coefficient of?0.951 and the RMSE?of 3.282. An independent?testing?sample set was used to evaluate the optimal model, the testing?correlation coefficient?was 0.903 and the RMSE was 4.128. We conclude that?NIR spectrometry is feasible to determine the octane in fuel petrol?by establishing SPA-LSSVM?models. The 1st-d’SG pretreatment has?the?advantage of selecting wavelengths containing the implicit information. The combination of 1st-d’SG pretreatment and SPA-LSSVM show its applicable potential to predict the?octane number?in?fuel petrol.展开更多
Background: toxic gases and fumes prompted from petrol and gas stations imply their disabling and deadly risks on human lungs. Aim of Work: The aim of this work was to assess the pulmonary function derangements in pet...Background: toxic gases and fumes prompted from petrol and gas stations imply their disabling and deadly risks on human lungs. Aim of Work: The aim of this work was to assess the pulmonary function derangements in petrol pump workers at Al-Medina Al-Munawara city. Patients and Methods: This cross sectional study was conducted on 189 cases out of them in control group (group I) with age and sex matched healthy adult males gathered from nonsmokers students and employees in Taibah University. The study group (group II) comprised of 89 males who were working in different petrol pump stations. History, clinical examination and pulmonary functional assessment were carried out by using portable spirometry, Co detector and puls oximeter. Results: The study’s results showoed that the lung function parameters (FEV1, FVC, PEFR, FEFR25% - 75%) were significantly reduced in petrol pump workers (Group II) as compared to the values for these parameters in subjects belonging to Group II (Control group), Similar findings were observed in previous studies on pulmonary functions in petrol-pump workers. This finding specified the restrictive nature of pulmonary involvement in the study group. Measurement of the exhaled CO was slightly higher in Group II than Group I. Conclusion: Fuel vapors and fumes in petrol stations showed direct incapacitating impact on workers pulmonary functions regarding spirometric measurements showing predominantly restrictive pattern and to less extent obstructive. Exhaled CO level was higher in addition to hypoxemia identified in these cases.展开更多
文摘Least square support vector machine (LSSVM) combined with successive projection algorithm (SPA) method was applied for?near-infrared (NIR)?quantitative determination of the octane number in fuel petrol. The NIR spectra of 87 fuel petrol samples were?scanned?for model establishment and optimization. First order derivative Savitzky-Golay smoother?(1st-d’SG) was?utilized to improve the?NIR predictive ability. Its pretreatment effect was compared with the raw data.?SPA was?applied for the extraction of informative wavelengths. Considering the linear and non-linear?training mechanism,?LSSVM?regression was employed to establish calibration models.?The correlation coefficient (R) and root mean square error (RMSE) were used as the model evaluation indices;accordingly the octane number in fuel petrol?was quantitatively determined with the prospective predictive indices. Results showed that?after pretreated by 1st-d’SG, 8 SPA-selected wavelengths?was generated as the inputs of LSSVM, so that the calibration models were optimized in the way of combining the SPA-LSSVM regression with the SG smoother.?The prediction results were quite satisfactory, with the calibrating correlation coefficient of?0.951 and the RMSE?of 3.282. An independent?testing?sample set was used to evaluate the optimal model, the testing?correlation coefficient?was 0.903 and the RMSE was 4.128. We conclude that?NIR spectrometry is feasible to determine the octane in fuel petrol?by establishing SPA-LSSVM?models. The 1st-d’SG pretreatment has?the?advantage of selecting wavelengths containing the implicit information. The combination of 1st-d’SG pretreatment and SPA-LSSVM show its applicable potential to predict the?octane number?in?fuel petrol.
文摘Background: toxic gases and fumes prompted from petrol and gas stations imply their disabling and deadly risks on human lungs. Aim of Work: The aim of this work was to assess the pulmonary function derangements in petrol pump workers at Al-Medina Al-Munawara city. Patients and Methods: This cross sectional study was conducted on 189 cases out of them in control group (group I) with age and sex matched healthy adult males gathered from nonsmokers students and employees in Taibah University. The study group (group II) comprised of 89 males who were working in different petrol pump stations. History, clinical examination and pulmonary functional assessment were carried out by using portable spirometry, Co detector and puls oximeter. Results: The study’s results showoed that the lung function parameters (FEV1, FVC, PEFR, FEFR25% - 75%) were significantly reduced in petrol pump workers (Group II) as compared to the values for these parameters in subjects belonging to Group II (Control group), Similar findings were observed in previous studies on pulmonary functions in petrol-pump workers. This finding specified the restrictive nature of pulmonary involvement in the study group. Measurement of the exhaled CO was slightly higher in Group II than Group I. Conclusion: Fuel vapors and fumes in petrol stations showed direct incapacitating impact on workers pulmonary functions regarding spirometric measurements showing predominantly restrictive pattern and to less extent obstructive. Exhaled CO level was higher in addition to hypoxemia identified in these cases.
