This paper presents a description and analysis of the most important models to predict each of the Road User Costs components (Vehicle Operating Costs, Accident Costs and Value of Time) and proposes a model for esti...This paper presents a description and analysis of the most important models to predict each of the Road User Costs components (Vehicle Operating Costs, Accident Costs and Value of Time) and proposes a model for estimating RUC components suitable for the Portuguese road network. These results are part of a research which aimed to obtain a Road User Cost Model to be used as a tool in road management systems. This model is different from other models by the fact that it includes a simple formulation that allows calibration and calculation of cost parameters, for any year, in a simple and fast way, providing trustworthy results. The required data is already available in Portuguese institutions, allowing periodic revision of cost parameters to insure accuracy.展开更多
Because pipeline has large pipe diameter, large throughout and high pressure, once pipeline leakage accident happens, the damage is quite serious. In addition, pipeline leakage accident caused by man-made drilling oil...Because pipeline has large pipe diameter, large throughout and high pressure, once pipeline leakage accident happens, the damage is quite serious. In addition, pipeline leakage accident caused by man-made drilling oil stolen every year results in huge economic losses on oilfield. Therefore, a real-time and accurate pipeline leak detection and location system not only can effectively decrease leakage loss and reduce the waste of manpower and material resources in patrolling work, but also is conductive to the management of oil pipeline and improvement of economic efficiency of enterprise. The paper determines leak detection and location project giving priority to negative pressure wave and supplemented by flow parameter analysis. The method not only can judge the accidence of leakage timely and accurately, but also can effectively avoid leakage false alarm caused by start or stop pumps in pipeline.展开更多
Transport risk assessment for the environment has two important aspects--problem solving model and solution veracity. Problem solving model is larger understanding of tasks interconnection, which represents in itself ...Transport risk assessment for the environment has two important aspects--problem solving model and solution veracity. Problem solving model is larger understanding of tasks interconnection, which represents in itself partial solution of general risk assessment. Veracity of solution means how the results are consistent with the reality. By researching of both aspects, it rises many unanswered questions. It is concerned about verification and validation of risk assessment results. By risk assessment for the environment it is possible to meet wide variety of more or less good soluble problems. It exists simple problems based on risk assessment of common traffic accidents connected with service charge outflow. On the other site, it exists complex problems of risk assessment connected with dangerous goods transport by traffic or pipelines. By simple problems solving there are not many questions about risk assessment veracity. It is possible to determine traffic accidents frequencies and service charge outflows consequences on the basis of examined events in transportation with great veracity. By complex problems the situation is quite different. The frequencies of large accidents are very low but the consequences for the environment may be large. Both are encumbered by large level of uncertainty. That is why the question is rising. To what degree, it is in these cases correct to make decision based on risk assessment.展开更多
Objective: Tracheobronchial injuries are defined as injuries involving the trachea and/or bronchi from the level of the cricoid cartilage extending up to the division of the bronchi. We present a case series with mos...Objective: Tracheobronchial injuries are defined as injuries involving the trachea and/or bronchi from the level of the cricoid cartilage extending up to the division of the bronchi. We present a case series with most of the tracheobronchial injuries found to be sustained after penetrating trauma. Methods: A retrospective review was performed at the Aga Khan University, Karachi, Pakistan. From January 2004 to December 2009, 168 patients with thoracic trauma were treated, of whom 15 were recognized to have major tracheobronchial and pulmonary injuries. Results: The average age was 3 l years with most of the patients being male (14:1). Among them,11 patients had penetrating trauma as the main cause of injury, 3 patients had blunt trauma from road traffic accidents, only 1 patient had combined trauma (blunt and penetrating trauma). Eightpatients were diagnosed based on radiological findings. All the patients were treated surgically. Lobectomy was the most common intervention performed in 7 patients. The mortality rate was 7% (1 patient). Most patients survived with no sequelae (10 patients) while 5 survived with disability. We found that penetrating trauma was the leading cause of injury in our series. The severity of injury depends upon the weapon causing the trauma. Patients in our series had multiple injuries and required surgical management. Conclusions: Tracheobronchial injuries are rare but potentially life threatening. They require quick diagnosis and management. Diagnosis tends to be difficult since there are no specialised diagnostic modalities available at present.展开更多
文摘This paper presents a description and analysis of the most important models to predict each of the Road User Costs components (Vehicle Operating Costs, Accident Costs and Value of Time) and proposes a model for estimating RUC components suitable for the Portuguese road network. These results are part of a research which aimed to obtain a Road User Cost Model to be used as a tool in road management systems. This model is different from other models by the fact that it includes a simple formulation that allows calibration and calculation of cost parameters, for any year, in a simple and fast way, providing trustworthy results. The required data is already available in Portuguese institutions, allowing periodic revision of cost parameters to insure accuracy.
文摘Because pipeline has large pipe diameter, large throughout and high pressure, once pipeline leakage accident happens, the damage is quite serious. In addition, pipeline leakage accident caused by man-made drilling oil stolen every year results in huge economic losses on oilfield. Therefore, a real-time and accurate pipeline leak detection and location system not only can effectively decrease leakage loss and reduce the waste of manpower and material resources in patrolling work, but also is conductive to the management of oil pipeline and improvement of economic efficiency of enterprise. The paper determines leak detection and location project giving priority to negative pressure wave and supplemented by flow parameter analysis. The method not only can judge the accidence of leakage timely and accurately, but also can effectively avoid leakage false alarm caused by start or stop pumps in pipeline.
文摘Transport risk assessment for the environment has two important aspects--problem solving model and solution veracity. Problem solving model is larger understanding of tasks interconnection, which represents in itself partial solution of general risk assessment. Veracity of solution means how the results are consistent with the reality. By researching of both aspects, it rises many unanswered questions. It is concerned about verification and validation of risk assessment results. By risk assessment for the environment it is possible to meet wide variety of more or less good soluble problems. It exists simple problems based on risk assessment of common traffic accidents connected with service charge outflow. On the other site, it exists complex problems of risk assessment connected with dangerous goods transport by traffic or pipelines. By simple problems solving there are not many questions about risk assessment veracity. It is possible to determine traffic accidents frequencies and service charge outflows consequences on the basis of examined events in transportation with great veracity. By complex problems the situation is quite different. The frequencies of large accidents are very low but the consequences for the environment may be large. Both are encumbered by large level of uncertainty. That is why the question is rising. To what degree, it is in these cases correct to make decision based on risk assessment.
文摘Objective: Tracheobronchial injuries are defined as injuries involving the trachea and/or bronchi from the level of the cricoid cartilage extending up to the division of the bronchi. We present a case series with most of the tracheobronchial injuries found to be sustained after penetrating trauma. Methods: A retrospective review was performed at the Aga Khan University, Karachi, Pakistan. From January 2004 to December 2009, 168 patients with thoracic trauma were treated, of whom 15 were recognized to have major tracheobronchial and pulmonary injuries. Results: The average age was 3 l years with most of the patients being male (14:1). Among them,11 patients had penetrating trauma as the main cause of injury, 3 patients had blunt trauma from road traffic accidents, only 1 patient had combined trauma (blunt and penetrating trauma). Eightpatients were diagnosed based on radiological findings. All the patients were treated surgically. Lobectomy was the most common intervention performed in 7 patients. The mortality rate was 7% (1 patient). Most patients survived with no sequelae (10 patients) while 5 survived with disability. We found that penetrating trauma was the leading cause of injury in our series. The severity of injury depends upon the weapon causing the trauma. Patients in our series had multiple injuries and required surgical management. Conclusions: Tracheobronchial injuries are rare but potentially life threatening. They require quick diagnosis and management. Diagnosis tends to be difficult since there are no specialised diagnostic modalities available at present.