Cashing in on Caching: An Architecture for Time-Bounded Knowledge-Based Problem Solving

Knowledge-based computing, in general, suffers from an inherent open-endedness that precludes its application in time-bounded domains where an answer must be computed within a stipulated time limit. We examine a two-way improvement of the shortcomings: a knowledge representation scheme that provides easy access to relevant knowledge and thereby reduces search time, and a reasoning scheme that is algorithmic in nature and thus makes computational requirements meaningfully estimable.In this work, we offer a cache-based architecture that is capable of both storing knowledge in different formats (e.g. rules, cases), and invoking an appropriate reasoning scheme to fit the available computing time. The cache helps in retrieving the most relevant pieces of knowledge (not only exact matches) required for solving a given problem. This cache relies on a reasoning tactic, knowledge interpolation, that can generate a solution from two near-matches in an algorithmic way, to generate time-bounded solutions. We illustrate the design of such a cache for solving resource allocation problems in the domain of shortwave radio transmission and evaluate its performance in observing imposed temporal bounds.     

基于ABAQUS软件的微米级金属材料性能研究

为工程实践中迫切需要解决微米和亚微米量级的设计与制造问题,文章中运用MSG塑性理论利用Abaqus软件对铝合金的强度及均匀延伸率进行了比较系统的研究;运用有限单元法分析了MSG应变梯度本构方程和经典的弹塑性本构方程对不同晶粒尺寸的铝合金的应力应变关系;模拟不同晶粒尺寸的铝合金的强度及均匀延伸率。结果表明随着晶粒尺寸的减小,屈服强度、应变硬化明显增加,延伸率却往往越小。对于该问题的研究探索,将是解决材料强度与均匀伸长率这对矛盾体的问题关键,同时,为科研工作者提供了新方法和新途径。     

梯度功能材料热弹性应力的分析方法

本文介绍了近年来国外有关梯度功能材料热弹性应力问题的最新研究方法，并对其方法特点进行了评述．     

Longwall mining automation horizon control:Coal seam gradient identification using piecewise linear fittingOA

Horizon control, maintaining the alignment of the shearer’s exploitation gradient with the coal seam gradient, is a key technique in longwall mining automation. To identify the coal seam gradient, a geological model of the coal seam was constructed using in-seam seismic surveying technology. By synthesizing the control resolution of the range arm and the geometric characteristics of the coal seam, a gradient identification method based on piecewise linear representation(PLR) is proposed. To achi...     

基于相对梯度的人脸识别方法

在原始相对梯度算子的基础上,提出一种新的相对梯度算子,并将它与二维主成分分析（2DPCA）或者二维Fisher线性判别分析（2DFLD）相结合,形成一种基于改进相对梯度算子的人脸识别算法。在AR库和Yale_B库上的实验表明,基于改进相对梯度算子的人脸识别算法对人脸图像的光照、表情等变化均具有较好的鲁棒性,识别准确率明显高于只用2DPCA或2DFLD进行特征抽取的人脸识别方法,以及基于原始相对梯度算子的人脸识别算法。同时采用三种不同大小的窗口分别进行实验,实验结果证明,当窗口大小为3×3时,识别效果相对最好。     

Can computers carry content ‘inexplicitly’?

I examine whether it is possible for content relevant to a computer's behavior to be carried without an explicit internal representation. I consider three approaches. First, an example of a chess playing computer carrying emergent content is offered from Dennett. Next I examine Cummins response to this example. Cummins says Dennett's computer executes a rule which is inexplicitly represented. Cummins describes a process wherein a computer interprets explicit rules in its program, implements them to form a chess-playing device, then this device executes the rules in a way that exhibits them inexplicitly. Though this approach is intriguing, I argue that the chess-playing device cannot exist as imagined. The processes of interpretation and implementation produce explicit representations of the content claimed to be inexplicit. Finally, the Chinese Room argument is examined and shown not to save the notion of inexplicit information. This means the strategy of attributing inexplicit content to a computer which is executing a rule, fails.I wish to thank Fred Dretske, JOhn Perry, and an anonymous reviewer for helpful comments and suggestions. Earlier versions of this paper were read at the American Philosophical Association Pacific Division Meeting in San Francisco in March, 1993, and at the 7th International Conference on Computing and Philosophy in Orlando in August, 1992.     

Formation of structure of the CdTe film, recrystallized on Mo/glass substrate under high temperature and mechanical pressure

Large-grained and 7 μm thick CdTe film has been fabricated on top of Mo coated soda-lime glass substrate. As a new approach the dynamic recrystallization process (DRC) was used to form the structure of films. For the characterization of the structure and composition of the films a scanning electron microscopy (SEM), energy dispersive X-ray microanalysis (EDS) and X-ray diffraction (XRD) methods were used. The changes in the structure of films were studied in accordance with the process temperature, pressure and as-deposited film thickness. Significant changes in the CdTe film were observed after DRC of deposited films at the process temperatures between 450 °C and 550 °C. EDS quantitative analysis showed that during the recrystallization the Mo and CdTe films composition remained stable for all studied samples. The XRD results showed that the increase in the process temperature caused improvement in orientation of the films along direction of (111). The DRC temperature above 550 °C reduced the orientation again. The limits of the temperature and pressure in application of soda-lime glass in DRC were found and discussed.     

Pseudo-Stokes Vector Correlation From Complex Signal Representation of a Speckle Pattern and Its Applications to Micro-Displacement Measurement

Abstract:  As an improvement of the intensity correlation used widely in conventional electronic speckle photography, we propose a new technique for displacement measurement based on correlating Stokes-like parameters derivatives for transformed speckle patterns. The method is based on a Riesz transform of the intensity speckle pattern, which converts the original real-valued signal into a complex signal. In closest analogy to the polarisation of a vector wave, the Stokes-like vector constructed from the spatial derivative of the generated complex signal has been applied for correlation. Experimental results are presented that demonstrate the validity and advantage of the proposed pseudo-Stokes vector correlation technique over conventional intensity correlation technique.     

Effect of carrier screening on ZnO-based resistive switching memory devices

The carrier screening effect occurs commonly in dielectric materials. It reduces the electric potential gradient, thus negatively affecting the functionality of resistive random access memory (RRAM) devices. An Au/ZnO film/Al-doped ZnO device fabricated in this work exhibited no resistive switching (RS), which was attributed to the carrier screening effect. Therefore, annealing was used for alleviating the screening effect, significantly enhancing the RS property. In addition, different on/off ratios were obtained for various bias values, and the screening effect was accounted for by investigating electron transport mechanisms. Furthermore, different annealing temperatures were employed to modulate the free carrier concentration in ZnO films to alleviate the screening effect. The maximal on/off ratio reached 10⁵ at an annealing temperature of 600 °C, yielding the lowest number of free carriers and the weakest screening effect in ZnO films. This work investigates the screening effect in RS devices. The screening effect not only modulates the characteristics of memory devices but also provides insight into the mechanism of RS in these devices.

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一种针对图像模糊的无参考质量评价指标

在成像模型的基础上,分析了图像模糊的原因,提出了一种为图像构造参考图像的方法,进而将结构相似度(SSIM)评价方法引入到无参考图像质量评价中,提出一种无参考结构清晰度(NRSS)的新的无参考图像质量评价方法,将其用于对模糊图像的质量评价。该方法通过低通滤波器来构造参考图像,通过计算原始图像与参考图像的结构相似度值来评价原始图像质量,很好地结合了成像系统的数学模型和结构相似度评价方法的优势,实验结果表明无参考结构清晰度评价指标能够给出和主观评价方法以及其余有参考评价方法一致的结果。