ON APPROXIMATION OF PERIODIC ATEB-FUNCTIONS

Two versions of approximation formulae for periodic Ateb-sine and Ateb-cosine in the first quarter of their common period are proposed. The first version is a Pade type approximation derived when constructing analytical solution of corresponding integral equation by iteration method with transforming the power series into a closed sum by Shanks’ formula. Two iteration approximations are considered. The first one is more concise but of worse approximation accuracy which deteriorates with increasing the argument value. To improve the approximation accuracy a hybrid approximation is proposed when the values of the Ateb-functions in the beginning (for the cosine) and in the end (for the sine) of the quarter period are computed by a separate formula obtained a priory by the asymptotic method. The comparison analysis of the approximate and exact values of the special functions indicates the error of the approximation proposed to be less than one per cent. The second variant of approximation is by replacing the periodic Ateb-functions by trigonometric functions of specific argument. The arguments are chosen so that the values of the special functions are exact at specific points of the quarter period. Five such collocation points are introduced in the paper. To implement this version of approximation a separate table of the values of the periodic Ateb-functions at the collocation points is compiled. The computational examples presented in the paper show the approximate values of the special functions obtained by the second version of approximation to have a good accuracy.

Ti(C,N)-Based Cermets: Critical Review of Achievements and Recent Developments

The paper describes briefly the historical development and presents in more detail solid-state properties such as hardness, heat conductivity, thermal expansion and mechanical properties of titanium carbonitride Ti (C,N), the basis of the hard phase of cermets. The metallurgy of Ti (C,N)-based cermets with respect to microstructure formation during sintering and the impact on properties are presented in more detail. The various influences such as W and/or Mo content, Mo/W ratio, C content and C/N ratio, binder phase content and binder phase composition (Co/Ni), sintering time, dwell time, alloy state of powders and grain size were critically evaluated and are presented in form of fracture toughness vs. hardness graphs. A table gives a reference list on the study of these influences. TRS data on cermets were collected and summarised in a separate table, too. The focus is put on grades which have the potential of being fabricated soon in industrial processes for production of cermet tools. Application examples for metal cutting, sawing and chip bonding are presented. In two final sections recent modifications and achievements such as graded microstructures, multicomponent binder, and hybrid microstructures are also briefly presented together with an outlook on the future potential of cermet applications.

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Alexey Alexandrovich saw nothing unusual or improper about his wife sitting with Vronsky at a separate table and talking animatedly about something; but he did notice that it seemed unusual and improper to everyone else in the drawing room, and for that reason it...

Brief overview of the apian virus taxonomy

The aim of this study was to analyze the information on the taxonomy of bee viruses in order to help the reader to navigate throughout this topic. Classification of bee viruses is a changing system. The best known bee viruses belong to the Dicistroviridae and Iflaviridae (Picornavirales; ssRNA +) families. Taxa from the Baculoviridae, Iridoviridae and Poxviridae families should be also considered as potential honeybee pathogens. English re-searchers have informed about 18 “important bee viruses.” 21 different apian virus taxa were blamed, among others, for honeybee losses in US apiaries, including 10 virus taxa considered as the most pathogenic. One of the most comprehensive descriptions of the known bee virus taxa has been provided in the materials of the Europe-an COLOSS project. Detailed data from all the above sources were shown in this review. We also analyzed the possibilities of the appearance of some honeybee-parasite viruses, as well as other insect viruses and plant virus-es in honeybees. A separate table provides information about the additional publications on the most important taxa of the apian viruses. The crucial role of V. destructor infestation for increased risk of viral infections and, therefore, the urgent need of research on apian virology and on ways of increasing of the honeybee immuni-ty/resistance has been indicated.

Screening Fruit Loosening Agents for Black Ripe Processed Table Olives

The California table olive (Olea europaea L.) industry relies exclusively on hand harvesting of its primary Manzanillo cultivar. Increased harvesting costs have intensified industry interest in identifying an abscission agent that can be used with developing mechanical harvesting technologies to increase removal rates. Table olives are harvested immature green at horticultural maturity but before physiological maturity. The goal of this research was to reevaluate the potential of ethylene-releasing compounds (ERCs) as olive-loosening agents and to screen additional candidates previously shown to accelerate citrus fruit abscission. Eleven compounds were screened at two separate table olive-growing sites (Fresno and Tehama counties) in California in September until Nov. 2006. Compounds were applied at various concentrations alone or in combination. Fruit detachment force (FDF) and percent fruit drop were measured and leaf loss assessed. Of the compounds evaluated, the ERC ethephon (2-chloroethyl phosphonic acid) and 1-aminocyclopropane-1-carboxylic acid were the most efficacious. In whole tree applications, concentrations of ethephon or 1-aminocyclopropane-1-carboxylic acid above 1000 mg·L−1 reduced FDF to less than 50% of the untreated control within 17 days, but leaf drop increased with increasing concentrations. Addition of 1-methylcyclopropene reduced efficacy of ethephon and delayed leaf drop. Monopotassium phosphate + ethephon (4% and 1000 mg·L−1, respectively) reduced FDF and leaf loss was equivalent to the ethephon alone treatment. Compounds such as methyl jasmonate, coronatine, dikegulac, MAXCEL, traumatic acid, and 5-chloro-3-methyl-4-nitro-1H-pyrazole were not efficacious.

Storm Water Best Management Practices that Maximize Aquifer Recharge

This article reviews and provides evaluation guidelines for six major storm water best management practices including bioretention areas, grassed swales/filter strips, infiltration trenches, porous pavement, rain barrels and wet detention ponds. A detailed table allows for quick and easy design comparisons, including a separate table which allows for site specific cost comparisons. A logic diagram is provided as a basic tool for screening the most feasible management practice.

A Dutch contribution to knowledge on phytosanitary risk and host status of various crops for Meloidogyne chitwoodi Golden et al., 1980 and M. fallax Karssen, 1996: an overview

The results of experiments, performed in The Netherlands during the last decade, on the host range of Meloidogyne chitwoodi and M. fallax are presented and discussed. Opinions are expressed on the host status of the tested plants and the phytosanitary status of the commercial product (defined as that part of the plant that enters trade) separately, as interest for both categories may differ. Information for each category is given for a variety of plants such as vegetables, arable crops, flowering bulbs and plants, and ornamental plants and trees. Data obtained from glasshouse experiments are given in a separate table. Many plants are a good host for one or both nematode species, and the commercial product, such as some bulbs and potatoes, might form a phytosanitary risk as a carrier of the juveniles inside the product, this risk being increased when that commercial product has roots.

Predicting Site Index for Old-Field Loblolly Pine Plantations

Height-over-age curves and site-index prediction tables were derived using nonlinear polymorphic regression models with data from 25-year-old old-field plantations ranging from coastal North Carolina to southwestern Arkansas. Plots from heavy silty clay soils of the interior flatwoods of Mississippi exhibited height growth patterns noticeably different from the overall pattern. A separate table and set of curves were developed for such sites.

Radiant-interchange configuration factors between various selected plane surfaces

The radiant-interchange configuration factor F1-2 (later referred to simply as ‘factor’) is defined as the fraction of the energy leaving an isothermal area Ax that is incident upon another area A 2. The validity of Lambert’s law of diffuse radiation is assumed. The calculation of such factors in the case of two rectangles having a common edge and forming an arbitrary angle is discussed, and a table of calculated values is presented. It is shown how the factors for two parallel, convex polygons, forming the bases of a right prism , can be derived from the results obtained for the rectangles. Values of such factors for a number of regular polygons are tabulated . A separate table gives factors for the honeycomb structure, much used in aviation and aerospace. The importance of much greater accuracy in the calculations than is generally thought necessary is shown by an example.