Identifying outliers with sequential fences

The identification of contaminated observations or outliers is an important part of data analysis since such observations can have a profound influence and distort the analysis. One simple graphical method, based on the box-plot, consists of constructing fences. The fences method is not only appealing in its simplicity but more importantly because it does not use the extreme potential outliers which can inflate the computing of a measure of dispersion and hence lessen the sensitivity for identifying outliers. The commonly used fences procedure may be too liberal in some situations and too conservative in others. That is, it sets one criteria for all scenarios and does not afford the data analyst the flexibility of specifying the probability or criterion for designating an observation as an outlier in a variety of circumstances. Furthermore, the most commonly used procedure is a “one size fits all” style and does not incorporate sample size. Unfortunately, a value that is extreme in a small data set might be expected in a much larger sample. In this paper, a method is proposed to include sample size in constructing fences as well as a sequential procedure to identify multiple outliers at a specified probability.     

Evaluation of uncertainties related to passive systems performance

A methodological and structured procedure to address the uncertainties related to passive safety functions is presented. The matter is treated with reference to a passive system designed for decay heat removal of advanced light water reactors, relying on natural circulation and provided with a heat exchanger immersed in a cooling pool, acting as heat sink, and connected to the pressure vessel via steam and condensate main lines. Two hazard identification used qualitative methods, as failure mode and effect analysis (FMEA) and hazard and operability study (HAZOP), are utilized and the relative results compared in order to assess the main sources of physical failure. The identification of the sources of uncertainties related to passive system performance, in terms of parameters which drive the failure mechanisms, follows. Finally the uncertainties are evaluated both for their assessment in probabilistic terms and for the determination of most contributors to the system thermal-hydraulic response.     

Cognitive networks: adaptation and learning to achieve end-to-end performance objectives

In this article we advance the idea of a cognitive network, capable of perceiving current network conditions and then planning, learning, and acting according to end-to-end goals. Cognitive networks are motivated by the complexity, heterogeneity, and reliability requirements of tomorrow's networks, which are increasingly expected to self-organize to meet user and application objectives. We compare and contrast cognitive networks with related research on cognitive radios and cross-layer design. By defining cognitive networks, examining their relationship to other technologies, discussing critical design issues, and providing a framework for implementation, we aim to establish a foundation for further research and discussion     

A Novel Needle Probe Based on High-Speed Complex Permittivity Measurements for Investigation of Dynamic Fluid Flows

For the investigation of multiphase or multicomponent flows, which are of interest, for instance, in oil extraction and processing or in chemical engineering, there are only few suitable measuring techniques. For this reason, we have developed a high-speed complex permittivity needle probe. Such probes are able to distinguish the different phases or components of a flow by measuring the complex value of the electrical permittivity at a high data rate (up to 20 000 samples/s). The performance of the system, as well as its ability to differentiate organic substances, has been analyzed. A time-resolved experiment in an oil-water-gas flow, as well as a two-substance mixing experiment in a stirred tank, is presented.     

Influence of Osmoconcentration, Continuous High-Frequency Ultrasound and Dehydration on Properties and Microstructure of Rabbiteye Blueberries

Rabbiteye blueberries were osmoconcentrated for 12 h, and for 3 h with and without continuous high-frequency ultrasound (CHFU) and then air dehydrated (70°C, 10 h). Osmoconcentration increased solids gain, moisture loss, soluble solids, and bulk density. Long osmoconcentration for 12 h can be reduced with CHFU with similar results. Scanning electron microscopy (SEM) micrographs indicated that berries without pretreatment suffered the highest degree of tissue collapse. They also had the highest rehydration ratio and may be ideal for use in breakfast cereals. Osmoconcentrated berries may be used as snack food or in cereal bars due to high bulk density and low rehydration ratio.     

An Efficient Macromodeling Approach for Simulating Carbon-Nanotube Field-Emission Triode Devices in Display Applications

The advances of using carbon-nanotube (CNT) triode structure field-emission (FE) devices for display applications require an accurate and efficient SPICE-compatible device model for evaluating their electrical behaviors in the early circuit and system design stage. This letter presents a simple and efficient macromodeling approach that can accurately model the CNT triode FE devices independent of the device process and physical structures for circuit simulations.     

Design of an end-to-end method to extract information from tables

This paper plans an end-to-end method for extracting information from tables embedded in documents; input format is ASCII, to which any richer format can be converted, preserving all textual and much of the layout information. We start by defining table. Then we describe the steps involved in extracting information from tables and analyse table-related research to place the contribution of different authors, find the paths research is following, and identify issues that are still unsolved. We then analyse current approaches to evaluating table processing algorithms and propose two new metrics for the task of segmenting cells/columns/rows. We proceed to design our own end-to-end method, where there is a higher interaction between different steps; we indicate how back loops in the usual order of the steps can reduce the possibility of errors and contribute to solving previously unsolved problems. Finally, we explore how the actual interpretation of the table not only allows inferring the accuracy of the overall extraction process but also contributes to actually improving its quality. In order to do so, we believe interpretation has to consider context-specific knowledge; we explore how the addition of this knowledge can be made in a plug-in/out manner, such that the overall method will maintain its operability in different contexts.The opinions expressed in this article are the responsibility of the authors and do not necessarily reflect those of Banco de Portugal.     

A fast and efficient hybrid fractal-wavelet image coder.

The excellent visual quality and compression rate of fractal image coding have limited applications due to exhaustive inherent encoding time. This paper presents a new fast and efficient image coder that applies the speed of the wavelet transform to the image quality of the fractal compression. Fast fractal encoding using Fisher's domain classification is applied to the lowpass subband of wavelet transformed image and a modified set partitioning in hierarchical trees (SPIHT) coding, on the remaining coefficients. Furthermore, image details and wavelet progressive transmission characteristics are maintained, no blocking effects from fractal techniques are introduced, and the encoding fidelity problem common in fractal-wavelet hybrid coders is solved. The proposed scheme promotes an average of 94% reduction in encoding-decoding time comparing to the pure accelerated Fractal coding results. The simulations also compare the results to the SPIHT wavelet coding. In both cases, the new scheme improves the subjective quality of pictures for high-medium-low bitrates.     

The effect of reprocessing on the properties of PVC

The effects of reprocessing on the mechanical, physical, and rheological properties of a commercial plasticized PVC compound are investigated. Reprocessing experiments at lower, identical, and higher temperatures than those attained during the initial extrusion in a capillary rheometer are undertaken. Repetitive reprocessing is also considered. With the exception of the mean surface roughness—and when the effects of degradation are discarded—the other characteristics of processed and reprocessed PVC are essentially similar. Nevertheless, changes at both the molecular and the morphological level take place during reprocessing, as demonstrated by the results of thermal analysis and surface appearance.     

A molecular model for the d chain of the giant haemoglobin from Lumbricus terrestris and its implications for subunit assembly

We have previously reported that rhodacyanine dyes, such as 1 and 2, exhibited a potent inhibitory effect on the growth of several tumor cells and that 4-oxothiazolidine (rhodanine) was an essential moiety for antitumor activity. On the basis of our foregoing work, two types of rhodacyanine dyes, which categorized into class I and II depending on the methine length, were synthesized and evaluated as a novel antitumor agent. Attention was particularly focused on the structure-activity study of two heteroaromatic rings. In class I, where the A rings were conjugated to rhodanine via two methine groups, compounds 1, 20, 23, and 24 were found to be efficacious in tumor-bearing nude mice model study, but they did not have the chemical properties (stability, solubility) suitable for clinical use. In contrast, in class II, where the A rings were directly conjugated to rhodanine, compounds 13 and 25, which possessed a benzothiazole moiety for the A ring, exhibited the favorable biological and chemical properties. Therefore, we decided to have a benzothiazole moiety as the A ring and introduce various heterocyclic groups for the B ring. As a result, the pyridinium ring was selected as the optimal moiety for the B ring (compound 13). Further, the variation of counteranion had a profound effect on solubility in water without influence on antitumor activity. Chloride anion was selected as the favorable anion with respect to synthetic method as well as solubility in water. Our study finally led us to the identification of compound 3 (MKT 077, 1-ethyl-2-[[3-ethyl-5-(methylbenzothiazolin-2-ylidene)-4-oxothi azolidin-2 -ylidene]methyl]pyridinium chloride) as the candidate for clinical trials and is currently subjected to further investigation as a potent antitumor agent in phase I clinical trial for the treatment of solid tumors.