A thin polymer insulator for Josephson tunneling applications

The use of an organic monolayer formed from a vapor as an insulating barrier for thin film Josephson junctions is considered, and the effect of an organic monolayer on the transition temperature of a thin film superconductor is investigated. Also analyzed are the geometric factors which influence Josephson junctions and Josephson junction interferometers

Estratigrafía y biofacies del Aptiense inferior de Cuchía (Cantabria, N. de España)

Se ha reevaluado la litoestratigrafía y el desarrollo de facies del Aptiense inferior de la parte central de la Cuenca Cantábrica Norte (CCN) y se ha dado un carácter formal a la Formación Caranceja del Aptiense inferior mediante la designación de un lectoestratotipo. Esta Formación esta compuesta por un Miembro inferior calcarenítico (calizas marinas someras), un Miembro medio margoso (margas de prodelta a zona más profunda de cuenca), y un Miembro superior de areniscas (sedimentos de delta). En respuesta al desarrollo de un episodio transgresivo, durante el (¿Barremiense terminal? -) Aptiense inferior, en la CCN se desarrolló un sistema de rampa carbonatada. Este sistema está representado por el Miembro inferior calcarenítico de la Formación Caranceja, cuya biofacies está netamente dominada por organismos heterótrofos (“carbonatos heterozoicos”). En el contexto de un clima subtropical húmedo, se considera que el que se produjese un fuerte impulso terrígeno rico en nutrientes fue el factor responsable de que se pudiesen dar carbonatos de condiciones más templadas en un ambiente de aguas cálidas. Poco después de que se hubiese establecido, el sistema de rampa carbonatada “juvenil” fue inundado en el Aptiense inferior. Los datos estratigráficos, sedimentológicos, geoquímicos y de biofacies sugieren que la inundación se produjo en respuesta a una tectónica sinsedimentaria asociada a un ascenso eustático del nivel del mar y a las perturbaciones ambientales relacionadas con un evento anóxico oceánico Ia (“oceanic anoxic event” - OAE) del Aptiense inferior. Así, el Miembro inferior calcarenítico queda recubierto por las margas de aguas más profundas del Miembro medio margoso de la Formación Caranceja. Más arriba en la sección, la presencia de una secuencia granocreciente y estratocreciente hacia techo sugiere la progradación de un sistema deltaico dominado por las mareas („Delta de Cuchia“) en el sector central de la CCN hacia el fi nal del Aptiense inferior. Todavía durante la parte terminal el Aptiense inferior tuvo lugar una nueva inundación de la CCN que permitió que se estableciese una plataforma carbonatada somera de carácter marginal, representada por la Formación calizas de San Esteban. Las micro- y biofacies de la Formación San Esteban sugieren un marco de lagoon con pequeños aportes terrígenos durante su sedimentación. Esta „Plataforma de San Esteban“ fue fragmentada por los movimientos tectónicos asociados al „evento Gargasiense“ durante al intervalo correspondiente al límite Aptiense inferior/superior

Prehistoric, and historic antecedents of a contemporary Ngamiland community

African Studies Center Working Paper No. 12INTRODUCTION: An archaeological survey was incorporated as part of a long-term project which I began in 1973. Fieldwork has been carried out during two periods: July, 1973 - January, 1974 and February, 1975 - May, 1976. The work is centered at /ai/ai (Nxai Nxai) in northwestern Ngamiland. Malan (1950) and Yellen (1975) made small collections at this waterhole. My investigations are designed to increase our understanding of the social ecology of the zu/oasi and Ovaherero peoples who live in this region. Periodic animal and plant censuses are recorded so that reasonably precise estimates of productivity of both wild and domesticated food resources may be calculated. Inventories of animals killed are kept on a daily basis and vegetable foods acquired are recorded on a randomly established schedule. A logbook is maintained in which are kept data pertaining to the social behavior of all residents at and visitors to zu/oasi. A number of indicators of nutritional status of both zu/oasi and Ovaherero individuals are monitored periodically. Short reports on the project have appeared (Wilmsen 1976a, 1976b, van der Walt et al., 1977). This report is confined to the current status of the archaeological program and its implications

Approach for the development and application of target process module sets

The implementation of agile frameworks, such as SAFe, in large companies causes conflicts between the overall product development process with a rigid linkage to the calendar cycles and the continuous agile project planning. To resolve these conflicts, adaptive processes can be used to support the creation of realistic target-processes, i.e. project plans, while stabilizing process quality and simplifying process management. This enables the usage of standardisation methods and module sets for design processes. The objective of this contribution is to support project managers to create realistic target-processes through the usage of target-process module sets. These target-process module sets also aim to stabilize process quality and to simplify process management. This contribution provides an approach for the development and application of target-process module sets, in accordance to previously gathered requirements and evaluates the approach within a case study with project managers at AUDI AG (N=21) and an interview study with process authors (N=4) from three different companies

METHOD for the IDENTIFICATION of REQUIREMENTS for DESIGNING REFERENCE PROCESSES

A reference process should consider to the needs and behaviours of the process users, as well as all relevant restrictions and boundary conditions within the company and its environment. Therefore, this contribution provides a method to synthesize relevant requirements on reference processes and supports the consideration of these requirements during the design of a new, company-specific reference process based on meta-models. The developed method was used to design a reference process for automotive predevelopment projects and its applicability and usefulness was evaluated successfully

Categories of Product Innovations. A Prospective Categorization Framework for Innovation Projects in Early Development Phases Based on Empirical Data

AbstractMost of the categorization frameworks for innovation projects in early development phases are not designed for supporting the product engineer in decision making and leave space for further improvement. Based on empirical data from 13 innovation projects, the authors introduce a novel categorization framework for innovation projects and discuss the relevance of identified key criteria. The focus is to provide a fundamental understanding of the varieties of product innovation projects and establish a basis for decision support frameworks regarding the adoption of tools and methods

Determination of mechanical stress distribution in Drosophila wing discs using photoelasticity

Morphogenesis, the process by which all complex biological structures are formed, is driven by an intricate interplay between genes, growth, as well as intra- and intercellular forces. While the expression of different genes changes the mechanical properties and shapes of cells, growth exerts forces in response to which tissues, organs and more complex structures are shaped. This is exemplified by a number of recent findings for instance in meristem formation in Arabidopsis and tracheal tube formation in Drosophila. However, growth not only generates forces, mechanical forces can also have an effect on growth rates, as is seen in mammalian tissues or bone growth. In fact, mechanical forces can influence the expression levels of patterning genes, allowing control of morphogenesis via mechanical feedback. In order to study the connections between mechanical stress, growth control and morphogenesis, information about the distribution of stress in a tissue is invaluable. Here, we applied stress-birefringence to the wing imaginal disc of Drosophila melanogaster, a commonly used model system for organ growth and patterning, in order to assess the stress distribution present in this tissue. For this purpose, stress-related differences in retardance are measured using a custom-built optical set-up. Applying this method, we found that the stresses are inhomogeneously distributed in the wing disc, with maximum compression in the centre of the wing pouch. This compression increases with wing disc size, showing that mechanical forces vary with the age of the tissue. These results are discussed in light of recent models proposing mechanical regulation of wing disc growth

Polarization properties in the transition from below to above lasing threshold in broad-area vertical-cavity surface-emitting lasers

For highly divergent emission of broad-area vertical-cavity surface-emitting lasers (VCSELs) a rotation of the polarization direction by up to 90 degrees occurs when the pump rate approaches the lasing threshold. Well below threshold the polarization is parallel to the direction of the transverse wave vector and is determined by the transmissive properties of the Bragg reflectors that form the cavity mirrors. In contrast, near-threshold and above-threshold emission is more affected by the reflective properties of the reflectors and is predominantly perpendicular to the direction of transverse wave vectors. Two qualitatively different types of polarization transition are demonstrated: an abrupt transition, where the light polarization vanishes at the point of the transition, and a smooth one, where it is significantly nonzero during the transition