SUMMARYThis paper presents a study for the development of a system capable of performing real-time pseudo dynamic testing. The system combines the basics of the pseudo dynamic test with a dynamic actuator, a digital displacement transducer and a digital servomechanism. The digital servo-mechanism has been introduced to ensure accurate displacement and velocity control, in which digital feedback control with a time interval of 2 msec has been performed continuously during actuator motion. Using the system, pseudo dynamic tests under sinusoidal and earthquake ground motion are carried out for a structure having a viscous damper, demonstrating that a perfectly real-time pseudo dynamic test can be achieved by incorporating the modified central difference method into an extra buffer operation of the digital servo-mechanism. The responses solved by the pseudo dynamic tests are compared with the responses of the test structure as well as those obtained from post-numerical analysis, and it is found that the real-time pseudo dynamic test conducted in this study is accurate.

Unsteady 3-D flows through two-stage stator-rotor cascade channels in a low-pressure steam turbine model developed by Mitsubishi Heavy Industry (MHI) are numerically and experimentally investigated assuming dry and wet-steam conditions. The fundamental equations for condensate flows derived by the authors are applied to the present flow computations. The high-order high-resolution finite-difference method based on the fourth-order compact MUSCL TVD (Compact MUSCL) scheme and the Roe’s approximate Riemann solver are used for the space discretization of convection terms. The pipelined LU-SGS scheme optimized for the parallel-implicit time-integration is also employed. MHI measured the total pressures, static pressures and yaw angles of flow velocity vectors at the outlet of first-stage rotor, second-stage stator, and second-stage rotor. The calculated results are compared with the experimental results. In addition, unsteady condensate mass fractions are numerically visualized and the influence of wakes and secondary vortices to the condensation is discussed.

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Unsteady 3-D flows through two-stage stator-rotor cascade channels in a low-pressure stearn turbine model developed by Mitsubishi Heavy Industry(MHI) are numerically investigated and compared with the experiments. The fundamental equations solved in this study are based on the compressible Navier-Stokes equation and the SST turbulence model in general curvilinear coordinates. 1[he high-order high-resolution finite-difference method based on the fourth-order compact MUSCL TVD(Compact MUSCL) scheme and the Roe's approximate Riemann solver are used for the space discretization ofconvection terms. A parallelized LU-SGS scheme based on the pipelining algorithn is also employed for the parallel-implicit time-integration. [[btal pressures, static pressures and yaw angles of flow velocity vectors at the otuIet of first-stage rotor, second-stage stator, and second-stage rotor obtained from the computation are compared with the corresponding experiments.Finally the reliability of both numerical and experimental appreaehes is discussed.

Factors predicting adverse events following implantation with wafers containing 1,3-bis(2-chloroethyl)-1-nitrosourea (carmustine, BCNU), which is used in local chemotherapy for malignant gliomas (MGs), are unknown. The association between cerebral edema (CE), which often occurs after implantation, and perioperative seizures, which are often observed in MG cases, is under debate. This study investigated risk factors for CE associated with BCNU wafer implantation and their relationship with perioperative seizures. A total of 31 surgical cases involving 28 adult patients who underwent BCNU wafer implantation for MGs were investigated and classified into those with and without postoperative transient CE. We assessed the correlations between CE caused by BCNU implantation and various factors, including postoperative epileptic seizures. World Health Organization (WHO) grade III MGs significantly affected postoperative CE ( p = 0.003) and the occurrence of seizures ( p = 0.0004). Factors predictive of postoperative seizures were WHO grade III MGs ( p = 0.0026), increased postoperative CE ( p = 0.0272), and history of preoperative seizures ( p = 0.0316). Postoperative CE, WHO grade III MGs, and a history of preoperative seizures might predict the postoperative occurrence of seizures, necessitating stringent management of seizures and CE in the affected patients.