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991.
Infra-red video sequences were taken of directly bonded silicon wafer pairs undergoing the razor blade crack length bond strength measurement in a specially designed jig. A series of tests were carried out under controlled atmospheres of nitrogen at various relative humidities. Analysis of the video images showed that the crack continues to propagate rapidly for several minutes after the blade has stopped moving, and that the presence of moisture has a strong positive influence on the rate of crack propagation under static loading. A new Maszara protocol is suggested based on modelling crack growth using our experimentally derived constants.  相似文献   
992.
Analysis of an in-plane micro-generator with various microcoil shapes   总被引:1,自引:1,他引:0  
This study presents an analysis of an in-plane micro-generator with various microcoil shapes and multiple aspects of coupling, and reports the fabrication of a prototype micro-generator. It is important to establish analytical solutions for the micro-generator to predict the induced voltage. These analytical solutions can be used to estimate the micro-generator power to reduce the experimental time and the cost. Understanding the physical meanings of the variables can optimize the structure of the micro-electromagnetic generator. This model considers electromagnetism, kinematics, and geometry. The proposed in-plane rotary electromagnetic micro-generator was fabricated using low-temperature co-fired ceramic technology to co-fire the silver microcoils on the ceramic substrate with different shaped coils (e.g., square-shaped, circle-shaped and sector-shaped) both with the printing linewidth and 100 μm spacing of these microcoils. A planar permanent magnet with an outer diameter of 9 mm and a thickness of 700 μm was sintered by Nd/Fe/B. Its residual induction is 1.4 T. The experimental data in this study can be compared with analytical solutions. Analytical results show that the micro-generator with a sector-shaped microcoil generates a maximum effective value of 218.127 mV induced voltage at 1395.34 rad/s. Experimental measurements show a close agreement with these analytical solutions.  相似文献   
993.
The Medical and Pharmaceutical industries have shown high interest in the precise engineering of protein hormones and enzymes that perform existing functions under a wide range of conditions. Proteins are responsible for the execution of different functions in the cell: catalysis in chemical reactions, transport and storage, regulation and recognition control. Computational Protein Design (CPD) investigates the relationship between 3-D structures of proteins and amino acid sequences and looks for all sequences that will fold into such 3-D structure. Many computational methods and algorithms have been proposed over the last years, but the problem still remains a challenge for Mathematicians, Computer Scientists, Bioinformaticians and Structural Biologists. In this article we present a new method for the protein design problem. Clustering techniques and a Dead-End-Elimination algorithm are combined with a SAT problem representation of the CPD problem in order to design the amino acid sequences. The obtained results illustrate the accuracy of the proposed method, suggesting that integrated Artificial Intelligence techniques are useful tools to solve such an intricate problem.  相似文献   
994.
Implicit Error Correction is a near Video-on-Demand (nVoD) schema that trades bandwidth utilization for initial playback delay while potentially allowing an infinite number of users. Additionally, it provides error protection without further bandwidth increase by exploiting the implicit redundancy of nVoD protocols, using linear combinations of the segments transmitted in a given time slot. This paper introduces a new implementation that outperforms the original schema by adding two new mechanisms: redundancy channels and feedback error correction.  相似文献   
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Interventional radiology procedures require extensive cognitive processing from the physician. A set of these cognitive functions are aimed to be replaced by technology in order to reduce the cognitive load. However, limited knowledge is available regarding mental processes in interventional radiology. This research focuses on identifying mental model–related processes, in particular during percutaneous procedures, useful to improve image guidance during interventions. Ethnographic studies and a prototype-based study were conducted in order to perform a task analysis and to identify working strategies and cognitive processes. Data were compared to theories from visual imagery. The results indicate a high level of complexity of mental model construction and manipulation, in particular when mentally comparing mental model knowledge with radiology images on screen (e.g., to steer a needle correctly). Regarding current interface support, most difficult is the interpretation and selection of oblique views. New interface principles are needed to bring cognitive demands within reasonable human range, and also accompanying cognitive work strategies should be developed.  相似文献   
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