Real-time condition monitoring is becoming an important tool in maintenance decision-making. Condition monitoring is the process of collecting real-time sensor information from a functioning device in order to reason about the health of the device. To make effective use of condition information, it is useful to characterize a device degradation signal, a quantity computed from condition information that captures the current state of the device and provides information on how that condition is likely to evolve in the future. If properly modeled, the degradation signal can be used to compute a residual-life distribution for the device being monitored, which can then be used in decision models. In this work, we develop Bayesian updating methods that use real-time condition monitoring information to update the stochastic parameters of exponential degradation models. We use these degradation models to develop a closed-form residual-life distribution for the monitored device. Finally, we apply these degradation and residual-life models to degradation signals obtained through the accelerated testing of bearings.

Uranium recovery from seawater was investigated in simulated seawater in the laboratory and in natural seawater from the coasts of China with different amidoximebased (AO) ultrahigh molecular weight polyethylene (UHMWPE) fibers. The capacities of adsorbents AO-UHMWPE-1 and -2 were 4.54 and 2.41 mg U/g-adsorbent, respectively, after 24 h of adsorption in the simulated seawater with 330 ppb U. Their capacities were 2.93 and 1.95 mg U/gadsorbent, respectively, after 42 days of adsorption in simulated seawater flow-through experiments with 3.3 ppb U. However, because of sediment and marine organism contamination, the capacities were 0.25 and 0.04 mg U/g-adsorbent, respectively, after 68 days of adsorption in natural seawater in Xiamen. The capacity of AO-UHMWPE-7 was 1.41 mg U/gadsorbent after 15 days of adsorption in natural seawater in Daishan. The average capacity of AO-UHMWPE-7 was 1.50 mg U/gadsorbent, which was 18 times greater than that for V after 15 days of adsorption in natural seawater in Daishan. Results indicated that there were many factors affecting the adsorption capacity of uranium. In addition to the character of the adsorbent, including degree of grafting, functional group density, and AO conversion ratio, the marine hydrological conditions, such as temperature, flow velocity, turbidity, etc., are also crucially important for uranium extraction from seawater.

The emerging video coding standard, High Efficient Video Coding (HEVC), aims at doubling coding efficiency of H.264/AVC. Fractional Motion Estimation (FME) in HEVC presents a significant challenge in clock latency and area cost as it consumes more than 40% of the total encoding time and its high computational complexity. Firstly, this paper proposes a fast interpolation filter algorithm, which is based on the 8-pixel interpolation unit. It can save 9.9% processing time on average while introducing only 0.1256% BD_PSNR coding quality degradation. Based on this, the paper designs and realizes the interpolation filter VLSI architecture with the reconfigurable configuration and the cell block reuse to reduce the implement hardware area. The final VLSI implementation only requires 64.5k gates in a standard 90nm CMOS technology at an operating frequency of 193MHz. The proposed architecture can be reused for halfpixel interpolation and quarter-pixel interpolation, which can reduce the area cost for about 131040 bits RAM. The processing latency of our proposed VLSI architecture can support the real-time processing of 4:2:0 format 3840×2160@47fps video sequences.

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Traditional computer system depends on access policy and user's identities to grant or deny their access to resources. The basic assumption in this system is the entities had been known. It is unsuitable to use identitybased access control in ubiquitous computing environment where entities are not foreknown to each other. In this paper, we present a trust based access control model to secure ubiquitous computing application. The resourceconstrained trust negotiation is addressed to establish initial trust for authenticating strangers. By the initial trust, each user is arranged a role subset, and context information dynamic decides which role is active.

In this paper, the conception and the construction of classification maps (CMs) are discussed. Methods called Fp mapping and Sp mapping are proposed based on discriminant analysis (DA) and projection pursuit (PP). By these methods, an experimental data set with classification information can be mapped from multidimensional data space onto a series two-dimensional projection keeping the original classification structure in the process. These projections show intuitively the semiquantitative relationships between the study object and its controlling factors that we cannot observe directly from multivariate data space. Based on existing experimental data, these methods are useful in giving valuable suggestions on further experimental works. As an example, they were applied to the study of a kind of propellant material and a kind of welding material and were proven effective in the optimization of the material's performance.

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