In this paper, a centralized deadlock detection algorithm with multiple outstanding requests (CDDMOR) is proposed for use in distributed database systems and transaction-processing systems. This algorithm allows a pro...
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In this paper, a centralized deadlock detection algorithm with multiple outstanding requests (CDDMOR) is proposed for use in distributed database systems and transaction-processing systems. This algorithm allows a pro...
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In this paper, a centralized deadlock detection algorithm with multiple outstanding requests (CDDMOR) is proposed for use in distributed database systems and transaction-processing systems. This algorithm allows a process to request many resources simultaneously. While a centralized scheme is superior to a completely distributed scheme in terms of performance, a major problem of such a scheme is congestion. Therefore, an important extension to the basic CDDMOR, a partially distributed scheme, is proposed to alleviate the problem of congestion, as well as to take advantage of the result presented by several researchers that global (multisite) deadlocks are infrequent. It takes care of the local (single site) deadlocks without involving other sites and uses centralized deadlock detection only when there is a possibility of global deadlock.
There are many university initiatives that focus on technology-based solutions to address the needs of marginalized communities. The technology-based solutions are intended to be economically and socially sustainable....
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Objective and Impact *** imaging of ultrasound and optical contrasts can help map structural,functional,and molecular biomarkers inside living subjects with high spatial *** is a need to develop a platform to facilita...
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Objective and Impact *** imaging of ultrasound and optical contrasts can help map structural,functional,and molecular biomarkers inside living subjects with high spatial *** is a need to develop a platform to facilitate this multimodal imaging capability to improve diagnostic sensitivity and ***,combining ultrasound,photoacoustic,and optical imaging modalities is challenging because conventional ultrasound transducer arrays are optically *** a result,complex geometries are used to coalign both optical and ultrasound waves in the same field of *** elegant solution is to make the ultrasound transducer transparent to ***,we demonstrate a novel transparent ultrasound transducer(TUT)linear array fabricated using a transparent lithium niobate piezoelectric material for real-time multimodal *** TUT-array consists of 64 elements and centered at~6 MHz *** demonstrate a quad-mode ultrasound,Doppler ultrasound,photoacoustic,and fluorescence imaging in real-time using the TUT-array directly coupled to the tissue mimicking *** TUT-array successfully showed a multimodal imaging capability and has potential applications in diagnosing cancer,neurological,and vascular diseases,including image-guided endoscopy and wearable imaging.
In a number of contexts relevant to control problems, including estimation of robot dynamics, covariance, and smart structure mass and stiffness matrices, we need to solve an over-determined set of linear equations AX...
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In a number of contexts relevant to control problems, including estimation of robot dynamics, covariance, and smart structure mass and stiffness matrices, we need to solve an over-determined set of linear equations AX /spl ap/ B with the constraint that the matrix X be symmetric and positive definite. In the classical least squares method, the measurements of A are assumed to be free of error. Hence, all errors are confined to B. Thus, the "optimal" solution is given by minimizing /spl par/AX - B/spl par//sub F//sup 2/. However, this assumption is often impractical. Sampling errors, modeling errors, and, sometimes, human errors bring inaccuracies to A as well. We introduce a different optimization criterion, based on area, which takes the errors in both A and B into consideration. The analytic expression of the global optimizer is derived. The algorithm is applied to identify the joint space mass-inertia matrix of a Gough-Stewart platform. Experimental results indicate that the new approach is practical, and improves performance.
This paper explores feedback controller design for cavity flows based on reduced-order models derived using Proper Orthogonal Decomposition (POD) along with Galerkin projection method. Our preliminary analysis shows t...
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This paper explores feedback controller design for cavity flows based on reduced-order models derived using Proper Orthogonal Decomposition (POD) along with Galerkin projection method. Our preliminary analysis shows that the equilibrium of the POD model is unstable and a static output feedback controller cannot stabilize it. We develop Linear Quadratic (LQ) optimal state feedback controllers and LQ optimal observers for the linearized models. The linear controllers and observers are applied to the nonlinear system using simulations. The controller robustness is numerically tested with respect to different POD models generated at different forcing frequencies. An estimation for the region of attraction of the linear controllers is also provided.
In this paper, we describe a user-oriented reliability model that addresses extensive web content, including many links, and that simultaneously addresses user dynamic navigation behaviour. Computation time is a probl...
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There exists a need for additional transmission capacity to connect distributed resources such as wind energy from remote locations to the power grid. The high cost of running transmission lines necessitates having a ...
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ISBN:
(纸本)9781424465460
There exists a need for additional transmission capacity to connect distributed resources such as wind energy from remote locations to the power grid. The high cost of running transmission lines necessitates having a way to minimize the length of transmission required to connect the distributed resources to load centers. In addition, the substations that connect to the transmission lines need to be fault tolerant by ensuring that the loss of any one transmission line does not result in the loss of power to any substation. In this paper, the relative cost of connecting a range of sources to a range of loads with and without fault tolerance is presented. Fault tolerance is achieved through a 2-path redundant graph approach. Studies show that the additional cost of ensuring fault tolerance for selected schemes ranges between 8% and 33%. This percentage value can support decision making in practice.
We report on focus group feedback regarding the services provided by existing education-related Digital Libraries (DL). Participants provided insight into how they seek educational resources online, and what they perc...
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In this work, we propose a 2TnC ferroelectric random access memory (FeRAM) cell design to realize the quasi-nondestructive readout (QNRO) of ferroelectric polarization (PFE) in a capacitor, which can relax the enduran...
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