Check! a generic and specific industrial inspection tool

The authors present an overview of an `inspection and control' package to perform automatic quality control of industrial components, specifically electronic circuit boards. This application has grown out of a set of tools designed initially to aid the development of point distribution models (PDMs) and grey-level models (GLMs) pioneered at the Wolfson Image Analysis Unit in Manchester. These models are both generic and specific. Generic, because they can be applied to most image classification problems; specific, because they aim at the full interpretation of the variability of the objects to be modelled. The underlying vision processing techniques are based on statistical pattern matching. Two synergetic approaches have been followed. The system is trained to recognise the components from either their shape or their grey level appearance or both     

From dust till drawn

We present a system for drawing pastel media in real-time as an effective alternative to most existing digital solutions that basically allow for drawing arbitrary strokes in a particular style. Our approach is focused on the simulation of the natural material itself and on its interaction with the drawing surface and the drawing tool. Upon free-form drawing, a bidirectional transfer of pigment takes place. In one direction, the paper surface is dusted with new pigment particles broken off the tip (i.e., the end of the drawing tool). A large part of these particles will be deposited or blended together with previously deposited ones whereas the remainder does not contribute to the drawing and is blown off. On the other hand, a certain amount of previously deposited pigment is scraped off and picked up again soiling the tip. This is noticeable in the next strokes to be drawn. Furthermore, both the tip and the paper surface are subject to weathering depending on the exerted pressure and friction of the drawing tool, and the bumpiness of the paper. As a result, the paper surface becomes slightly damaged, limiting the deposition of new pigment. The tip, on the other hand, becomes blunt making new strokes wider. From a stylistic point of view, similarly to traditional drawings our results convey the artists’ characteristics (e.g., the way of wielding the brush, skillfulness, feeling for the medium). Therefore, we believe that our system allows an artist to create realistically looking pastel images without losing his/her personal touch.     

The S-kernel: A measure of symmetry of objects

In this paper we introduce a new symmetry feature named “symmetry kernel” (SK) to support a measure of symmetry. Given any symmetry transform S, SK of a pattern P is the maximal included symmetric sub-set of P for all directions and shifts. We provide a first algorithm to exhibit this kernel where the centre of symmetry is assumed to be the centre of mass. Then we prove that, in any direction, the optimal axis corresponds to the maximal correlation of a pattern with its symmetric version. That leads to a second algorithm. The associated symmetry measure is a modified difference between the respective surfaces of a pattern and its kernel. A series of experiments supports the actual algorithm validation.     

Two-Way Protocol with Imperfect Devices

The security of a deterministic quantum scheme for communication, namely the LM05 [1], is studied in presence of a lossy channel under the assumption of imperfect generation and detection of single photons. It is shown that the scheme allows for a rate of distillable secure bits higher than that pertaining to BB84 [2]. We report on a first implementation of LM05 with weak pulses.     

造纸毛毯的发展与应用

本文拟就１９６３年至今我国造纸毛毯的生产和应用技术的发展和现状及造纸毛毯清洗系统的关键技术问题进行了综述，并就造纸毛毯的合理使用，使其发挥最佳功能提出了若干建议。     

廊固凹陷异常压力与天然气的分布和产出关系

重点阐述异常压力对天然气的分布影响关系。以冀中地区廊固凹陷第三系地层为研究对象，对异常压力的分布特征、天然气聚集区的异常压力与天然气产量关系等进行了分析。通过分析认为，异常压力与天然气分布聚集规律有着密切联系，分析的天然气分布聚集与产出规律对勘探开发有指导作用。     

Concomitant activation of MEK-1 and Rac-1 increases the proliferative potential of thyroid epithelial cells, without affecting their differentiation

Activating point mutations in the Ras oncogene occur in a large number of human tumors, especially of epithelial origin. In thyroid follicular cells, ectopic expression of oncogenic H-Ras results in growth factor-independent proliferation, loss of differentiation and tumor formation in nude mice. In fibroblasts concomitant activation of the MAP kinase cascade and the small GTPase Rac-1 leads to full malignant transformation. We have tested the effects of these key downstream mediators of Ras in thyroid epithelial cells, by stably expressing either a constitutively active form of MEK-1 (MEK(deltaN3/S218E/S222D)), a constitutively active form of Rac-1 (Val12-Rac), or both. While the activation of one molecule or the other results in a weak phenotype, concomitant activation of both MEK-1 and Rac-1 in thyroid cells leads to growth factor-independent proliferation, morphological transformation and anchorage-independent growth. However, in contrast to Ras-transformed thyroid cells, the ones expressing the constitutively active forms of MEK-1 and Rac-1 maintain their differentiate phenotype and fail to form tumors when injected into nude mice. Thus, in thyroid epithelial cells, concomitant activation of MEK-1 and Rac-1 can reproduce only a subset of the Ras-induced effects and is not sufficient to cause full malignant transformation. Significantly, Ras-mediated increased proliferation and loss of differentiation can be dissociated in these cells.     

Thermodynamics of inositol hexakisphosphate interaction with human oxyhemoglobin

The interaction of inositol hexakisphosphate (IHP) with oxygenated human adult hemoglobin (Hb) was investigated at 25 degreesC. The affinity of IHP for oxygenated Hb is strongly pH-dependent, and potentiometric measurements of proton uptake and release upon IHP addition have shown that over the range between pH 8.0 and pH 6.0 in oxygenated Hb there are three groups of residues that change their pKa values after IHP addition, likely because of their interaction with negative charges of the heterotropic effector. On the basis of previous calculations on the electrostatic properties of human Hb (Matthew, J. B., Hanania, G. I. H., and Gurd, F. R. N. (1979) Biochemistry 18, 1919-1928; Lee, A. W.-m., Karplus, M., Poyart, C., and Bursaux, E. (1988) Biochemistry 27, 1285-1301), two of these groups might be Val1beta and His143beta, which are located in the beta1beta2 dyad axis, where they have been also proposed to interact with 2,3-diphosphoglycerate, whereas the third group does not appear easily identifiable. Calorimetric measurements of the heat associated with IHP binding at different pH values over the same range indicate that IHP binding is mostly enthalpy-driven at pH < 7 and mostly entropy-driven at pH > 7.     

Necessary conditions for asymptotic tracking in nonlinear systems

In the literature, it has been shown that if a single-input single-output analytic nonlinear plant 1) has a well-defined relative degree and 2) is minimum-phase, it is possible to achieve asymptotic tracking for an open set of output trajectories containing the origin in C^N [0, ∞), the space of N-times continuously differentiable functions taking values in R. When either of these sufficient conditions is not met, various authors have investigated approximate analytic solutions, discontinuous solutions and solutions for restricted sets of trajectories. In this paper, it is shown that conditions 1) and 2) are necessary for the existence of an analytic compensator which yields asymptotic tracking for an open set of output trajectories. Analogous results are established for multi-input multi-output systems