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991.
0 引言智能仪表只要在速度允许的情况下 ,采用软件设计方法来替代部分硬件电路的方式 ,常会使其具有成本低、体积小、功能丰富、可靠性强、精度高等方面的优点。本文介绍SD - 1智能酸碱测量仪中采用的软件技术 ,实践证明效果很好。1 SD -1智能酸碱测量仪酸碱测量仪 (简称 pH计 )广泛应用在石化、电站、冶金、医药、环保和食品等行业 ,常用来测量物质的酸碱度。我们在查阅和参考国内外的资料和产品的基础上 ,成功研制出了SD - 1型智能酸碱监测仪。该仪表具有自诊断、自动确定标样、自动校准、自动调零、溶液温度自动 /手动检测及补… 相似文献
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To determine the maximum separation between events for nonrepetitive systems with max and linear constraints, there are the
“iterative tightening from above” (ITA) approach and the “iterative tightening from below” (ITB) approach. Since such systems
can be formulated as systems constrained by min–max inequalities, this paper gives an algorithm named MMIMaxSep for solving min–max inequalities. The algorithm is a generalization and a mathematically elegant reformulation of Yen et
al.’s MaxSeparation algorithm which uses the ITB approach. Our numerical experiments indicate that MMIMaxSep is very efficient. Moreover, MMIMaxSep has a unique advantage of being able to directly handle tree-represented min–max functions, and its complexity is closely
related to the complexity of computing cycle time of min–max functions.
相似文献
Yiping ChengEmail: |
994.
Chang CW Peng SC Cheng WY Liu SH Cheng HH Huang SY Chang YC 《Proteomics. Clinical applications》2007,1(11):1499-1512
Postsynaptic densities (PSDs), isolated from porcine cerebral cortices, are large disk-shaped aggregates consisting of hundreds of different proteins. To study the protein-protein interactions in such complex supramolecules, we developed a procedure to break up the PSD's overall structure, while preserving some interactions between individual proteins. Using the resulting PSD sample and an indirect immunoabsorption procedure, PSD-95 was isolated along with the α- and β-subunits of calcium calmodulin-dependent protein kinase II (CaMKIIα and CaMKIIβ), α-tubulin, β-tubulin, and Chapsyn110. Similarly, CaMKIIα was isolated along with CaMKIIβ, α-tubulin, β-tubulin, and small amounts of PSD-95. The proteins isolated from PSDs treated with a cleavable bifunctional crosslinking reagent were further subjected to diagonal gel electrophoresis analysis, and the results indicated that CaMKIIα resides next to α-tubulin in the PSD. Overall, the results obtained here suggest that within the PSD, large aggregates of CaMKIIα, CaMKIIβ, α-tubulin, and β-tubulin may occur that indirectly associate with PSD-95 and Chapsyn110. Such a protein organization would allow interactions with F-actin in the cytoplasm and with proteins, such as N-methyl-D-aspartate receptors, which reside on the postsynaptic membrane. Furthermore, it would facilitate binding to proteins such as the various microtubule-associated proteins that reside in the core region of the PSD. 相似文献
995.
On the removal of shadows from images 总被引:3,自引:0,他引:3
Finlayson GD Hordley SD Lu C Drew MS 《IEEE transactions on pattern analysis and machine intelligence》2006,28(1):59-68
This paper is concerned with the derivation of a progression of shadow-free image representations. First, we show that adopting certain assumptions about lights and cameras leads to a 1D, gray-scale image representation which is illuminant invariant at each image pixel. We show that as a consequence, images represented in this form are shadow-free. We then extend this 1D representation to an equivalent 2D, chromaticity representation. We show that in this 2D representation, it is possible to relight all the image pixels in the same way, effectively deriving a 2D image representation which is additionally shadow-free. Finally, we show how to recover a 3D, full color shadow-free image representation by first (with the help of the 2D representation) identifying shadow edges. We then remove shadow edges from the edge-map of the original image by edge in-painting and we propose a method to reintegrate this thresholded edge map, thus deriving the sought-after 3D shadow-free image. 相似文献
996.
Recent studies have employed simple linear dynamical systems to model trial-by-trial dynamics in various sensorimotor learning tasks. Here we explore the theoretical and practical considerations that arise when employing the general class of linear dynamical systems (LDS) as a model for sensorimotor learning. In this framework, the state of the system is a set of parameters that define the current sensorimotor transformation-the function that maps sensory inputs to motor outputs. The class of LDS models provides a first-order approximation for any Markovian (state-dependent) learning rule that specifies the changes in the sensorimotor transformation that result from sensory feedback on each movement. We show that modeling the trial-by-trial dynamics of learning provides a substantially enhanced picture of the process of adaptation compared to measurements of the steady state of adaptation derived from more traditional blocked-exposure experiments. Specifically, these models can be used to quantify sensory and performance biases, the extent to which learned changes in the sensorimotor transformation decay over time, and the portion of motor variability due to either learning or performance variability. We show that previous attempts to fit such models with linear regression have not generally yielded consistent parameter estimates. Instead, we present an expectation-maximization algorithm for fitting LDS models to experimental data and describe the difficulties inherent in estimating the parameters associated with feedback-driven learning. Finally, we demonstrate the application of these methods in a simple sensorimotor learning experiment: adaptation to shifted visual feedback during reaching. 相似文献
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In this paper we consider the single machine batch scheduling problem with family setup times and release dates to minimize
makespan. We show that this problem is strongly NP-hard, and give an
time dynamic programming algorithm and an
time dynamic programming algorithm for the problem, where n is the number of jobs, m is the number of families, k is the number of distinct release dates and P is the sum of the setup times of all the families and the processing times of all the jobs. We further give a heuristic with
a performance ratio 2. We also give a polynomial-time approximation scheme (PTAS) for the problem. 相似文献
1000.