In order to measure left ventricular regional wall motion and wall thickening, one must accurately track regional movement of the epicardial and endocardial borders. Here, the authors describe a computer-assisted tech...
详细信息
In order to measure left ventricular regional wall motion and wall thickening, one must accurately track regional movement of the epicardial and endocardial borders. Here, the authors describe a computer-assisted technique for tracking regional wall movement using "dynamic M-mode" images that combine the spatial continuity of 2-D cineloops with the temporal continuity of M-mode images. Measurements made using this technique are more accurate than those made from 2-D stop-frame images and have significantly lower interobserver differences than measurements made on either 2-D images or conventional M-mode hardcopy charts.
Previous work has shown that left atrial pressure can be non-invasively measured from mitral regurgitation velocity at the onset of left ventricular ejection. Here, the authors introduce a computer assisted approach t...
详细信息
Previous work has shown that left atrial pressure can be non-invasively measured from mitral regurgitation velocity at the onset of left ventricular ejection. Here, the authors introduce a computer assisted approach to computing left atrial pressure based on this technique which reduces the need for manual measurement of times and velocities from the Doppler spectra. This process includes the creation of a signal-averaged mitral regurgitation Doppler spectrum that combines data from multiple beats into a single, more coherent spectrum, with a more clearly delineated velocity envelope.
This paper discusses problems of identifying and estimating the reliability of complex real production systems in the constructing industry. The influence of the system structure on its reliability has been considered...
详细信息
This paper discusses problems of identifying and estimating the reliability of complex real production systems in the constructing industry. The influence of the system structure on its reliability has been considered. Types of elements and their connections in the system from the point of view of system reliability have been identified. The simulation method presented here allows to investigate the reliability of real systems, including the occurrence of inertia, variability of their structure and mutual dependence of reliability parameters of their elements. Two synthesis algorithms, (considering phase inertial in the estimation of system reliability), have been proposed and compared. On the basis of a machine system (loader-conveyor belt-material receiver), the utilisation of inertia to improve reliability characteristics of the system has been proved to be more effective than adding reserve elements to the system.
We present a pulse-driven asynchronous logic gate family based on a high-speed, low-power Josephson-junction device of rapid single-flux-quantum (RSFQ) circuits. Dual-rail logic is used and clock-free operation is rea...
详细信息
We present a pulse-driven asynchronous logic gate family based on a high-speed, low-power Josephson-junction device of rapid single-flux-quantum (RSFQ) circuits. Dual-rail logic is used and clock-free operation is realized. The proper operation of the circuits is confirmed by the numerical simulation which shows logic delays are about 60 ps for an AND and about 80 ps for an XOR. Power consumption is estimated to be 10 /spl mu/W/gate.
Harder, new requirements are appearing in the area of database systems. The popularity reached by parallel database systems during the past decade, due to their high performance and scalability characteristics, should...
详细信息
Harder, new requirements are appearing in the area of database systems. The popularity reached by parallel database systems during the past decade, due to their high performance and scalability
Harder, new requirements are appearing in the area of database systems. The popularity reached by parallel database systems during the past decade, due to their high performance and scalability
Proper distribution of operations among parallel processors in a large scientific computation executed on a distributed-memory machine can significantly reduce the total computation time. In this paper, we propose an ...
详细信息
Proper distribution of operations among parallel processors in a large scientific computation executed on a distributed-memory machine can significantly reduce the total computation time. In this paper, we propose an operation called simultaneous parallel reduction(SPR), that is amenable to such optimization. SPR performs reduction operations in parallel, each operation reducing a one-dimensional consecutive section of a distributed array. Each element of the distributed array is used as an operand to many reductions executed concurrently over the overlapping array's sections. SPR is distinct from a more commonly considered parallel reduction which concurrently evaluates a single reduction. In this paper we consider SPR on Single Instruction Multiple Data (SIMD) machines with different interconnection networks. We focus on SPR over sections whose size is not a power of 2 with the result shifted relative to the arguments. Several algorithms achieving some of the lower bounds on SPR complexity are presented under various assumptions about the properties of the binary operator of the reduction and of the communication cost of the target architectures.
Guaranteeing reproducibility and minimizing probe effects are major issues in the parallel program debugging. The paper suggests a new debugging method, called the Detect and Reproduce method, for message-based parall...
详细信息
暂无评论