Generalized current distribution rule

Method helps determine branch current in parallel-series network in relation to total input current by inspection. Method is particularly useful for circuits with many elements when branch elements are described as admittances. If element values are variables, then these values may be expressed as admittances to find currents readily in desired branches

Invariant and polynomial identities for higher rank matrices

We exhibit explicit expressions, in terms of components, of discriminants, determinants, characteristic polynomials and polynomial identities for matrices of higher rank. We define permutation tensors and in term of them we construct discriminants and the determinant as the discriminant of order $d$, where $d$ is the dimension of the matrix. The characteristic polynomials and the Cayley--Hamilton theorem for higher rank matrices are obtained there from

Young and very young stars in NGC 3372, the Carina nebula

Results are presented of a large-scale imaging photometric study of the stellar population in the northern part of NGC 3372 with a w avelength co verage from 0.33 to 2.5 µm. All observations were made at Las Campanas Observatory . The sizes of the three stellar clusters, Tr 14, Tr 15 and Tr 16, were determined b y means of star counts. Two-colour and colour-magnitude diagrams are presented and analyzed for eac h individual cluster. The three clusters were found to b e at a similar distance from the Sun, = 2 . 7 kpc, but with very large scatter in both A V and d . suggesting drastic variations in intracluster dust densit y . Dust particle size distribution variations are eviden t resulting in wide variations in extinction law. We determined ages bet ween 3 and 60 million years for Tr 15 and bet ween less than 1 and 6 million years for Tr 14 and Tr 16. The Tr 14 cluster is partially em bedded in a dense molecular cloud that extends to wards the south west reaching its highest densit y some three arcmin from the cluster nucleus. The ric h UV field created b y the Tr14 stars ionizes most of the visible HI I region in its vicinit y and most of the radio HI I region Car I. Deep J H K images of the Car I region reveal the presence of a young, em bedded stellar population that includes several O9–B0 stars and an ultracompact HI I region.Fil: Tapia, M.. Universidad Nacional Autónoma de México; MéxicoFil: Roth, M.. Las Campanas Observatory; ChileFil: Vazquez, Ruben Angel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica la Plata; ArgentinaFil: Persi, P.. IASFC, CNR; Itali

Validating adequacy and suitability of business-IT alignment criteria in an inter-enterprise maturity model

Aligning requirements of a business with its information technology is currently a major issue in enterprise computing. Existing literature indicates important criteria to judge the level of alignment between business and IT within a single enterprise. However, identifying such criteria in an inter-enterprise setting – or re-thinking the existing ones – is hardly addressed at all. Business-IT alignment in such settings poses new challenges, as in inter-enterprise collaborations, alignment is driven by economic processes instead of centralized decision-making processes. In our research, we develop a maturity model for business-IT alignment in inter-enterprise settings that takes this difference into account. In this paper, we report on a multi-method approach we devised to confront the validation of the business-IT alignment criteria that we included in the maturity model. As independent feedback is critical for our validation, we used a focus group session and a case study as instruments to take the first step in validating the business-IT alignment criteria. We present how we applied our approach, what we learnt, and what the implications were for our model

Developing an inter-enterprise alignment maturity model: research challenges and solutions

Business-IT alignment is pervasive today, as organizations strive to achieve competitive advantage. Like in other areas, e.g., software development, maintenance and IT services, there are maturity models to assess such alignment. Those models, however, do not specifically address the aspects needed for achieving alignment between business and IT in inter-enterprise settings. In this paper, we present the challenges we face in the development of an inter-enterprise alignment maturity model, as well as the current solutions to counter these problems