Quantitative criterion of the spatial inhomogeneity of the electromagnetic field in the near-field zone of a loop radiator

This paper presents a new algorithm for estimating the spatial inhomogeneity of images that is characterized by the number of patterns in a definite zone, their surface areas, and the efficient gradient between them. The use of this algorithm for quantifying the spatial inhomogeneity of the electromagnetic field of different loop radiators for radiofrequency hyperthermia showed that an applicator in the form of a circular arc produces a more inhomogeneous field than an applicator with a rectilinear profile.     

Adaptive methods and system for image processing

We present results obtained in the implementation of adaptive methods and a system for image processing. The light-developing nonlinear elements are used in the filtering block of the mirror optical configuration. The processing of gray-scale and of binary images with the help of adaptive optical elements is fulfilled for realization of ground-suppressing, contouring, differentiating, and skeletonizing adaptive filters. A comparison is made between optical and digital methods applied in the pattern processing.     

The SHARC framework for data quality in Web archiving

Web archives preserve the history of born-digital content and offer great potential for sociologists, business analysts, and legal experts on intellectual property and compliance issues. Data quality is crucial for these purposes. Ideally, crawlers should gather coherent captures of entire Web sites, but the politeness etiquette and completeness requirement mandate very slow, long-duration crawling while Web sites undergo changes. This paper presents the SHARC framework for assessing the data quality in Web archives and for tuning capturing strategies toward better quality with given resources. We define data quality measures, characterize their properties, and develop a suite of quality-conscious scheduling strategies for archive crawling. Our framework includes single-visit and visit?Crevisit crawls. Single-visit crawls download every page of a site exactly once in an order that aims to minimize the ??blur?? in capturing the site. Visit?Crevisit strategies revisit pages after their initial downloads to check for intermediate changes. The revisiting order aims to maximize the ??coherence?? of the site capture(number pages that did not change during the capture). The quality notions of blur and coherence are formalized in the paper. Blur is a stochastic notion that reflects the expected number of page changes that a time-travel access to a site capture would accidentally see, instead of the ideal view of a instantaneously captured, ??sharp?? site. Coherence is a deterministic quality measure that counts the number of unchanged and thus coherently captured pages in a site snapshot. Strategies that aim to either minimize blur or maximize coherence are based on prior knowledge of or predictions for the change rates of individual pages. Our framework includes fairly accurate classifiers for change predictions. All strategies are fully implemented in a testbed and shown to be effective by experiments with both synthetically generated sites and a periodic crawl series for different Web sites.     

On some weight functions admitting (0, 2) quadrature formulae with a high algebraic degree of precision

The purpose of this paper is to find a class of weight functions μ for which there exist quadrature formulae of the form (1) $$\int_{ - 1}^1 {\mu (x) f(x) dx \approx \sum\limits_{k = 1}^n {(a_k f(x_k ) + b_k f''(x_k ))} }$$ , which are precise for every polynomial of degree 2n.     

Design issues of a distance learning course on Business on the Internet

Abstract The paper presents the main design issues of a distance learning course on Business on the Internet. The instructional design is based on a learner-centred instructional strategy which allows learners to construct their own knowledge while solving real business problems and transferring their knowledge to other learners. They learn autonomously taking the responsibility for their learning and following their individual cognitive styles, interests, preferences. The learners have access to the Internet being members of a global, cooperative learning community. The learning community involves students and tutors who collectively take responsibility for the design and evaluation of the course content and the teaching methods to be applied. Both students and tutors inhabit a virtual learning environment that offers different virtual places and services: virtual university, virtual enterprise, auditoriums, workshop rooms, cafes, libraries, etc. where students from different locations can meet, interact, learn and work together, as if they were face-to-face.     

Synthesis and structure of large single crystalline silver hexagonal microplates suitable for micromachining

We report a simple one-step synthesis method of large single crystalline Ag (111) hexagonal microplates with sharp edges and a size of up to tens of microns. Single silver crystals were produced by reduction silver nitrate aqueous solution with 4-(methylamino)phenol sulfate. Scanning and transmission electron microscopy, energy-dispersive X-ray spectroscopy, selected area electron diffraction and optical microscopy techniques were combined to characterize the crystals. It is shown that the microplates can be easily dispersed and transferred as single objects onto different substrates and subsequently used as a high quality plasmonic starting material for micromachining of future nanocomponents, using modern top-down techniques like focused-ion beam milling and gas injection deposition.     

A model study of a conventional fixed bed tubular reactor with a catalyst layer on the inside tube wall

Mathematical simulation of a novel design of tubular reactor, supplied with a conventional fixed bed of catalyst and a catalyst layer on the inside tube wall, is carried out. The oxidation process of o-xylene to phthalic anhydride is investigated, using the kinetics of Calderbank and co-workers. In comparison with the conventional fixed bed reactor the new design displays several advantages, namely: higher productivity, better selectivity, relieved temperature regime, longer catalyst life, and shorter tubes.     

绿色能源与绿色工业(英文)

<正>A New AUsing the Modified Four Point Probe (Mo4PP) as a Tool for Monitoring Processing of Solar Cell Wafers 1 Modified Four Point Probe The aim of this report is to present and justify a new tool (Mo4PP) for Monitoring processing of solar cells.     

Existence and uniqueness of Hermite-Birkhoff Gaussian quadrature formulas

Quadrature formulas with arbitrary (Hermitian or Birkhoff) fixed nodes and free Hermitian nodes are studied. Existence of unique location for the free nodes is established such that they are all of Gaussian type.     

Catalytic activity of Fe/AC, obtained by impregnation of activated carbon in aqueous and non-aqueous media, to neutralize NO

The influence of the nature of the impregnating solutions media (aqueous or non-aqueous) on the forming of active phases is investigated in case of preparing iron catalysts, supported on activated carbon with respect to their catalytic activity in the reaction of NO reduction by CO. The catalysts are characterized by chemical analysis (AAS), BET surface area, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), magnetic susceptibility, and Mössbauer spectroscopy (MS). The catalytic investigations and TPD are carried out in a flow apparatus. Three peculiarities are observed with respect to this influence—the ratio between the separate iron species in different oxidation state of Fe species, which build up the catalytic active complexes (CAC), common participation of superficial groups of the carbon support and Fe components of the impregnating solutions as well as different dispersion of the active phase on the surface of the samples. As a result the highest catalytic activity was observed with the sample, obtained by impregnation with an aqueous solution, while with the other samples, obtained from organic solutions, the catalytic activity decreases in the order of: Methanol > Ethyl Ether > Acetone. It was assumed that the different catalytic activities are connected most probably with the process of forming of CAC during the process of preparation of the samples.