This study proposes a dynamic response analysis procedure for traffic-induced vibration of a monorail bridge and train. Each car in the monorail train is idealized as a dynamic system of 15-degrees-of-freedom. The governing equations of motion for a three-dimensional monorail bridge-train interaction system are derived using Lagrange's formulation for monorail trains, and a finite element method for modal analysis of monorail bridges. Analytical results on dynamic response of the monorail train and bridge are compared with field-test data in order to verify the validity of the proposed analysis procedure, and a positive correlation is found. An interesting feature of the monorail bridge response is that sway motion is caused by torsional behavior resulting from eccentricity between the shear center of the bridge section and the train load.
This paper introduces an analytical procedure to derive equations of motion for the monorail train-bridge interaction based on Lagrange's formulation to investigate riding comfort of moving monorail trains on bridges. A 15DOF dynamic model is assumed for a car in a monorail train that consists of driving, steering, and stabilizing wheels. It is based on the finite element method for modal analysis using three-dimensional models for a monorail bridge. Dynamic behaviors of a rationalized monorail bridge with a simplified structural system are investigated in comparison with those of a conventional monorail bridge using the developed analytical method. Riding comfort of running trains on the rationalized monorail bridge based on ISO2631 is estimated using 1/3 octave band spectral analysis. Observations indicate that a rational type bridge does not engender difficulties related to the riding comfort of the monorail train, even when considering the longest traveling time of passengers between terminals.
Background. There has been extensive use of serum tumor markers in diagnosing pancreatic adenocarcinoma. There is no tumor marker, however, that alone has sufficient diagnostic accuracy. It is necessary to know which combination of tumor markers should be used to detect pancreatic cancer, with respect to clinical usefulness and cost effectiveness.
Methods. Serum levels of 17 kinds of tumor markers were determined in 145 patients and 40 healthy volunteers. Thirty‐five patients with proven pancreatic adenocarcinoma, and 32 with benign pancreatobiliary disease (14 chronic pancreatitis and 18 biliary stones) were selected. For analysis of the usefulness of each tumor marker to differentiate these two groups, scatterplot and relative operating characteristic (ROC) analyses were used. A multivariate discriminant system to differentiate these two groups was developed using stepwise discriminant analysis by backward elimination selection.
Results. The significance of each tumor marker varied according to the tumor volume. By ROC analysis, the markers were divided into four subgroups according to their usefulness in discriminating pancreatic adenocarcinoma from benign pancreatobiliary disease. A discriminant system consisting of two different discriminant functions using nine tumor markers (CA 19–9, DUPAN‐2, TPA, elastase‐1, lipase, amylase, γ‐glutamyl transpeptidase, alkaline phosphatase, and lactate dehydrogenase) was developed and designated CAMPAS‐P; it could differentiate between all 35 cases of pancreatic adenocarcinoma and 32 cases of benign pancreatobiliary disease. On the other hand, CAMPAS‐P showed a low positive rate in pancreatic tumors of unusual histologic type, and poor organ‐specific diagnostic ability in various digestive organ malignancies.
Conclusions. CAMPAS‐P may be very useful for differential diagnosis between pancreatic adenocarcinoma and benign pancreatobiliary disease.
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