Sensor placement for diagnosability

The concept of diagnostic accuracy is examined and redefined to support specific criteria for sensor placement. If the correctness of diagnoser operation is assumed, then any failure to diagnose accurately must be attributable to an inadequacy of sensor data. Inaccuracy in diagnoses can be expressed solely in terms of additional candidates whose faults cannot be ruled out. With ambiguity as the determiner of the quality of a diagnosis, user-defined diagnosability requirements can be expressed in terms of the types and instances of components which are permissible exceptions to perfect diagnosis. This requires a working diagnoser and a simulator, along with sets of system configurations, component fault modes, potentially measurable parameters, and uniqueness requirements for fault isolation. From these, the diagnosability of individual components can be determined for a particular attached subset of the available sensors. An optimum sensor assignment is one that satisfies the most requirements with a fixed number of sensors or, conversely, that minimizes the sensor requirements to achieve a given threshold of diagnosability. The considerable complexity of this search is reduced by exploiting sensor set minimality, structural knowledge, and diagnosis-free extension to the system level. Global optimization and sensor allocation do not add to the number of diagnoses required for diagnosability analysis. Finally, corrective measures are discussed for use when residual costs remain too high, or when redundancy is too low.In support of NASA's Marshall Space Flight Center and the Space Station Freedom Advanced Development Program under NASA contract number NAS 8-37200.     

Oncological outcomes of operative treatment of subcutaneous soft-tissue sarcomas of the extremities

We reviewed the cases of sixty-two patients who had had a subcutaneous sarcoma to determine the effect of tumor and treatment-related variables on the rates of survival and local recurrence. Fifty-nine (95 per cent) of the patients had had an operation at another hospital before being referred to us. Twenty-nine (47 per cent) of the sixty-two tumors were high-grade, forty-two (68 per cent) were small (five centimeters or less), and thirty (48 per cent) were malignant fibrous histiocytomas. We followed a treatment strategy that consisted of repeat excision with the goal of obtaining wide margins. Excluding thirteen patients who had had a palpable local recurrence at the time of presentation, twenty (49 per cent) of forty-one patients who had had a marginal excision at another hospital had microscopic residual tumor on repeat excision. At a median of fifty-six months after the repeat excision, fifty (81 per cent) of the sixty-two patients had been continuously disease-free, one had no evidence of disease, eight had died of the disease, and three had died of other causes. The five-year rate of disease-free survival was 85 per cent (fifty-three of sixty-two patients). There were three local recurrences, all in patients who had had a marginal resection. No recurrences were noted in patients who had had a wide local excision of the tumor or of the previous operative field. Multivariate analysis revealed that a large tumor (greater than five centimeters), a marginal excision, and adjuvant radiation therapy were associated with a worse prognosis. Excellent rates of survival for patients who have a subcutaneous sarcoma, including those who have a large or high-grade tumor and those who have residual tumor following a previous operation, can be obtained with carefully planned operative treatment alone. We recommend operative excision or repeat excision with wide margins because of the high prevalence of residual tumor. Size is the most important tumor-related factor, and the operative margin is the most important treatment-related factor. The additional value of adjuvant radiation therapy remains unproved.     

Electro‐optical transfer function preferences for LCD TVs: The effect of display brightness and surround illumination on preferred gamma

Abstract— Recent commercial liquid‐crystal‐display (LCD) televisions are larger and brighter than traditional televisions, thus impacting the viewing conditions in which they are viewed. These changes in viewing conditions may require different electro‐optical transfer functions (EOTFs) for LCD TVs than those for conventional TVs. Here, the way various EOTFs affect the preferred image quality of test images with changes in brightness and surround illumination conditions are examined. The first method used a gain, offset, and gamma (GOG) function with a range of gamma values, and the second method altered the intrinsic EOTFs. Image preference for the simulated EOTFs was determined using a paired‐comparison experiment for ten images. The first experiment took place in a darkened room at two display luminance levels. The results indicated that a gamma of 1.6 was most preferred overall although more so at a lower screen luminance level. In a second experiment, the procedure was repeated with a dim surround of 10% of the display's white point. With this surround, preference for a gamma value of around 1.6 at both screen luminance levels was more enhanced. These results indicated that image preference for different EOTFs is dependent on display luminance and that this dependence is maintained with a dim surround.     

On the Wetting States of Low Melting Point Metal Galinstan® on Silicon Microstructured Surfaces

The primary goal of this article is to measure the wetting characteristics of a low melting point metal to determine the efficacy of this type of material for possible use in thermal energy storage applications. Galinstan®, a commercially available alloy consisting of Gallium, Indium, and Tin is subjected to contact angle measurements on various silicon surfaces at varying temperatures. Due to the oxidation characteristics of Galinstan, all experiments are conducted in an inert nitrogen environment (<0.5 ppm oxygen) to maintain fluid‐like properties. This work finds that although contact angle changes with substrate and surface structure, temperature has no observable effect on contact angle. Contact angles range from 141° on smooth silicon to greater than 160° on silicon micropillars. Although a temperature dependence is not observed over the range of temperatures studied, having wetting properties of Galinstan on various surfaces is a step toward better understanding the capabilities of this and similar materials in energy management.

     

下一代显示接口新标准--DisplayPort

随着显示技术逐渐转移到高性能的平板以及微电子技术,业界需要一种可扩充、开放产业标准的数字接口,以及可以把功能升级的解决方案。这种可升级的显示接口,应能满足企业以及一般消费者的各种需求。DisplayPort就是这种下一代的显示接口,可以为PC、监视器、显示面板、投影仪、以     

Converting Alkali Lignin to Biofuels over NiO/HZSM‐5 Catalysts Using a Two‐Stage Reactor

A series of NiO/HZSM‐5 catalysts were used to convert alkali lignin to hydrocarbon biofuels in a two‐stage catalytic pyrolysis system. The results indicated that all NiO/HZSM‐5 catalysts reduced the content of undesirable phenols, furans, and alcohols of the biofuel compared to non‐catalytic treatment. The NiO/HZSM‐5 catalyst with the lowest amount of NiO generated the highest biofuel yield in all catalytic treatments, and it also produced biofuel with the highest content of hydrocarbons. The emission of carbon oxides (CO and CO₂) increased in the treatments with higher‐NiO loading HZSM‐5 due to the redox reaction between NiO and the oxygenated compounds in the bio‐oil. Ni₂SiO₄ was generated in the used NiO/HZSM‐5 catalysts during the high‐temperature pyrolysis process.     

Computational models of germanium point contact detectors

In the crystal bulk of group IV covalent semiconductors such as germanium (Ge), simple analytic models for the valence band structure can provide fast, accurate computations of hole mobility for moderate energy ranges up to a few eV. On the surfaces of these materials, such as on Ge-vacuum or Ge-GeO₂ interfaces, the transport rates differ significantly from the bulk. This can be problematic for both point contact and segmented Ge gamma ray detectors, that require accurate carrier drift rates for computing signal basis sets, which themselves are necessary for the precise determination of gamma-ray induced compton scattering events. While several techniques exist for computing surface hole mobilities, more often than not, these methods are complex to implement, require significant computational resources, and lack the simplicity of bulk models for interpreting results. This paper presents a new technique for computing Ge surface hole mobility that can give a first estimate for the surface transport rates after tuning a physically based computational parameter. This model is used in conjunction with particle-in-cell (PIC) simulations for modeling hole-dynamics inside a Ge p-type point contact detector. The results of our calculations agree with experimental data gathered from Ge p-type point contact detectors at Oak Ridge National Laboratory.     

Logic programming to predict cell fate patterns and retrodict genotypes in organogenesis

Caenorhabditis elegans vulval development is a paradigm system for understanding cell differentiation in the process of organogenesis. Through temporal and spatial controls, the fate pattern of six cells is determined by the competition of the LET-23 and the Notch signalling pathways. Modelling cell fate determination in vulval development using state-based models, coupled with formal analysis techniques, has been established as a powerful approach in predicting the outcome of combinations of mutations. However, computing the outcomes of complex and highly concurrent models can become prohibitive. Here, we show how logic programs derived from state machines describing the differentiation of C. elegans vulval precursor cells can increase the speed of prediction by four orders of magnitude relative to previous approaches. Moreover, this increase in speed allows us to infer, or ‘retrodict’, compatible genomes from cell fate patterns. We exploit this technique to predict highly variable cell fate patterns resulting from dig-1 reduced-function mutations and let-23 mosaics. In addition to the new insights offered, we propose our technique as a platform for aiding the design and analysis of experimental data.     

ZerNet: Convolutional Neural Networks on Arbitrary Surfaces Via Zernike Local Tangent Space Estimation

In this paper, we propose a novel formulation extending convolutional neural networks (CNN) to arbitrary two-dimensional manifolds using orthogonal basis functions called Zernike polynomials. In many areas, geometric features play a key role in understanding scientific trends and phenomena, where accurate numerical quantification of geometric features is critical. Recently, CNNs have demonstrated a substantial improvement in extracting and codifying geometric features. However, the progress is mostly centred around computer vision and its applications where an inherent grid-like data representation is naturally present. In contrast, many geometry processing problems deal with curved surfaces and the application of CNNs is not trivial due to the lack of canonical grid-like representation, the absence of globally consistent orientation and the incompatible local discretizations. In this paper, we show that the Zernike polynomials allow rigourous yet practical mathematical generalization of CNNs to arbitrary surfaces. We prove that the convolution of two functions can be represented as a simple dot product between Zernike coefficients and the rotation of a convolution kernel is essentially a set of 2 × 2 rotation matrices applied to the coefficients. The key contribution of this work is in such a computationally efficient but rigorous generalization of the major CNN building blocks.