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A new diagnosis equipment is designed to examine the strength of large scale bridge. It is composed of three accelerometers, radio modem, and related electronics parts. Two accelerometers with high accuracy are used for measuring the change of inclination angle of the structure base and two horizontal components of structure vibration. The third accelerometer measures a vertical component of vibration. The equipment is installed in the sidewalk of some Moscow bridges as an application. Several factors such as traffic load, wind, water wave, and etc. cause the vibration of bridge. By means of appropriate processing, the spectral characteristics of the bridge itself are determined. Several month’s test shows that the spectral characteristics remains constant if the bridge state keeps constant, and is changed by the change of the bridge state (for example, before and after repair). If the measured inclination angle of the base is increased to a particular orientation, or the spectrum of bridge is changed, it is assumed that the sagging of the structure base or deformation of its structural members might happen. Periodic or continuous monitoring of the structure state under in-service condition with the help of this diagnosis equipment makes it possible to reveal the beginning of destructive changes in structural members and to prevent the occurrence of an emergency. The study result could be applied to other large structures such as towers and buildings.

In the case of a long-stator linear drive, unlike rotative drives for which speed or position sensors are a single unit attached to the shaft, these sensors extend along the guideway. The position signals transmitted from a maglev vehicle cannot meet the need of the real-time propulsion control in the on-ground inverter power substations. In this paper the design of the propulsion inverter control system with a position estimator for driving a long-stator synchronous motor in a high-speed maglev train is proposed. The experiments have been carried out at the 150 m long guideway at the O-song test track. To investigate the performance of the position estimator, the propulsion control system with, and without, the position estimator are compared. The result confirms that the proposed strategy can meet the dynamic property needs of the propulsion inverter control system for driving long-stator linear synchronous motors.

Purpose: Post-voiding residual urine hasbeen evaluated by urethral catheterization or abdomen ultrasonography in patients with benign prostatic hyperplasia. However, urethral catheterization is invasive and abdomen ultrasonography is not cost-effective for patients with benign prostatic hyperplasia. Therefore, we wished to determine the efficacy of using transrectal ultrasonography for the evaluation of the residual urine volume. Materials and Methods: A total of 37 patients were evaluated. The mean age of the patients was 69 years, ranging from 54-84 years. The empty bladder was instilled with a random volume of saline. In addition, the bladder volume was checked by transrectal ultrasonography. Results: The total mean residual urine volume checked by transrectal ultrasonography and catheterization were different statistically. When we performed a simple linear regression of the residual urine volume determined by each method, the regression coefficient was 0.699 and the determination coefficient was 58.4%. We divided the patients into two groups one group of patients with a residual urine volume of 150ml and the other group of patients with a prostate volume of 40ml. When the residual urine volume was less than 150ml and the prostate volume was less than 40ml, each mean residual urine volume was not different statistically. The determination coefficient was more than 60% by the simple linear regression. Conclusions: We could use transrectal ultrasonography for the purpose of a residual urine volume check. Especially when the residual urine volume was less than 150ml and the prostate volume was less than 40ml, we could estimate the residual urine volume by transrectal ultrasonography more accurately. (Korean J Urol 2007;48:951-955)