1,745 research outputs found
Una descripción inédita de Guayaquil
Get PDF4 p.La gran descripción de Guayaquil, la mejor de todas, es la que en 1774 hizo el ingeniero don Francisco Requena, a quien se deben también un plano del puerto, un mapa de toda la provincia y numerosos informes sobre su situación defensiva, sanitaria, etc. (obra publicada por Mª Luisa Laviana en Historiografía y Bibliografía Americanistas, XXVI, 1982, y reeditada como libro por la Escuela de Estudios Hispano-Americanos en 1984). Pero ahora damos a conocer una pequeña descripción que con el título de “Relación de Guayaquil y plano de la ciudad” se encuentra en el Servicio Histórico Militar de Madrid. Tiene el indudable valor de proporcionar una rápida y pintoresca visión del Guayaquil de la década de 1770, a la vez que su misma brevedad facilita su publicación.Peer reviewe
Coastal evolution of a Holocene barrier spit (Bug peninsula/NW-Rügen) deduced from geological structure and relative sea-level
Get PDFDie an der südwestlichen Ostseeküste gelegene Halbinsel Bug/NW Rügen wurde untersucht, um die Entwicklung von Haken und Nehrungen unter dem Einfluss des holozänen Meeresspiegelanstiegs zu studieren. Als Datengrundlage dienten 25 Sedimentkerne, sowie sieben Georadar- und sechs Sedimentecholotprofile, aus denen sechs Lithofaziestypen abgeleitet wurden. Danach besteht die Nehrung aus einer durchschnittlich 10 m mächtigen holozänen Sedimentfolge, die auf pleistozäner Basis aus Geschiebemergel und (glazi-)fluviolimnischen Feinsanden lagert. Obwohl keine absoluten Altersdaten gewonnen wurden, kann die Sedimentabfolge mit der lokalen relativen Meeresspiegelkurve problemlos korreliert und eine Modellvorstellung für die Nehrungsentwicklung geschlussfolgert werden. Die marine Inundation des Untersuchungsgebietes erfolgte um 7.000 BC während der Littorina-Transgression. In diesem Stadium stieg der Meeresspiegel rapide an und generierte einen schnell wachsenden Akkumulationsraum, in dem feinklastisches Material an oder unter der Wellenbasis akkumulierte und zu einem Reliefausgleich beitrug. Akkumulative Küstenformen bildeten sich nur in geringem Maße, da der Akkumulationsraum schneller wuchs als er durch das aus der Küstenerosion stammende Material aufgefüllt werden konnte. In dem Maße, indem der Meeresspiegelanstieg sich verlangsamte, gewann die Akkumulation an Bedeutung und der Hauptteil der Nehrung wurde innerhalb von rund zweitausend Jahren landfest. Entsprechend dem Verlauf von Strandwällen auf seiner heutigen Oberfläche lassen sich zwei Entwicklungsphasen aushalten, die von unterschiedlichen wellenenergetischen, erosiven und overwash-Prozessen bestimmt werden. Gegenwärtig besitzt die Nehrung ein Volumen von 66,4 Mio m³, woraus sich auf einen Rückgang des benachbarten Kliffs von rund 2000 m schließen lässt. Obwohl die Nehrung entwicklungsmäßig in ihrem Reifestadium angelangt zu sein scheint, deuten einige Merkmale auf zunehmende Instabilität hin. Im nördlichen Bereich verhindern Küstenschutzmaßnahmen einen Nehrungsdurchbruch und beginnende Auflösung. Im Süden haben Fahrwasserbaggerungen eine weitere Längenzunahme und das Zusammenwachsen mit Haken von Hiddensee verhindert. Ohne diese Maßnahmen würde die Nehrung durch Seegattbildung und zunehmende Erosion im Norden und Seegattschließung und zunehmende Uferprogradation im Süden eine neue Gestalt annehmen
a structure-activity correlation
Get PDFThe polymerization of octamethylcyclotetrasiloxane (D4) is investigated using
several five-, six- and seven-membered N-heterocyclic carbenes (NHCs). The
catalysts are delivered in situ from thermally susceptible CO2 adducts. It is
demonstrated that the polymerization can be triggered from a latent state by
mild heating, using the highly nucleophilic
1,3,4,5-tetramethylimidazol-2-ylidene as organocatalyst. This way, high
molecular weight PDMS is prepared (up to >400 000 g/mol, 1.6 < ÐM < 2.5) in
yields >95%, using low catalyst loadings (0.2–0.1 mol %). Furthermore, the
results suggest that a nucleophilic, zwitterionic mechanism is in operation,
in preference to purely anionic polymerization
The Use of the Concept “Entitlement” in Management Literature: A Historical Review, Synthesis, and Discussion of Compensation Policy Implications
Get PDFIndividuals\u27 perceptions of what they are entitled to have long been regarded as an important area of debate. We examine the various uses of entitlement perceptions across fields to develop a typology that identifies two dimensions: employee entitlement perceptions and reciprocity in the employee–employer relationship. We discuss how our typology informs management practice. In particular, we describe the implications of our typology on employee reactions to different pay plans. Directions for future research are suggested
A STUDY ON SUSTAINABLE BUILDING DEVELOPMENT IN THE CONTEXT OF TRANSITION FROM CONSTRUCTION 4.0 TOWARDS 5.0
Get PDFThe aim of this study is to to analyse the theoretical framework of Industry 4.0 and Industry 5.0 and their implications for the construction industry, as well as explaining their possible effects, by using an empirical research based on the existing scientific literature.
Industry 4.0 is an under-researched area in the construction industry, even though this field has a high benefit for the parties involved. Industry 5.0, on the other hand, stands for direct cooperation between robots or intelligent machines and humans. According to the ideas of the European Commission, Industry 5.0 consists of a triad: human orientation, sustainability and resilience.
Since this paper represents an outcome of an early PHD research, the methodology chosen was examining other similar research in the literature of Industry 4.0 and Industry 5.0 in the construction industry, new established concepts (such as Building Information Modeling, Product Lifecycle Management, sustainability)
Antibacterial Effects of Modified Implant Abutment Surfaces for the Prevention of Peri-Implantitis—A Systematic Review
Get PDFThe aim of the present study was to systematically review studies investigating antibacterial implant abutment surfaces or coatings, which may suppress bacterial growth to prevent plaque-induced peri-implant inflammatory disease. Data were collected after identification of case, assay/laboratory procedure, predicate/reference standard and outcome (CAPO). Seven hundred and twenty (720) records were identified through data base searching. After screening nine publications fulfilled inclusion criteria and were included. The following surfaces/coatings showed antibacterial properties: Electrochemical surface modification of titanium by the anodic spark deposition technique; doxycycline coating by cathodic polarization; silver coating by DC plasma sputter; titanium nitride; zirconium nitride and microwave assistant nano silver coating. Since the current state of the literature is rather descriptive, a meta-analysis was not performed. While several abutment coatings showed to have antibacterial capacity, some of them also influenced the behavior of investigated human cells. None of the studies investigated the long-term effect of surface modifications. Since surface changes are the main contributing factor in the development of antibacterial effects, the biodegradation behavior must be characterized to understand its durability. To date there is no effective structure, material or strategy to avoid peri-implant inflammation used as clinical routine. Furthermore, clinical studies are scarce
MEASURING AND INDICATING THE LEVEL OF INFORMATION SECURITY – AN ANALYSIS OF CURRENT APPROACHES
Get PDFIn times of increasing digitalization of processes in companies the topic of information security has become relevant for every industry. For this, a standardization of information security with normative standards such as ISO/IEC 27001:2022 has been established to define requirements and to assess at regular intervals the conformity of the management systems. However, practice shows that companies are fulfilling the requirements only at a minimum level and don’t have a real overview of their security level and the impact of existing risks. This paper evaluates how decision makers in companies currently interpret their security level using metrics. Regarding this, the relationship with effectiveness and conformity of their information security measures are shown and analyzed. Furthermore, in this paper a selection of the most common used practices and frameworks for measuring and certifying information security systems has been analyzed. The results of this research show that there is a need for on overall security perspective and include a proposal on how a structured approach should be defined
Detmold Conference Week 2017
Get PDFSince 2000 (in the beginning 21st Century) climate change and globalisation have influenced the actual
world and all societies tremendously and the have also affected the way we are building. Safety and
security requirements are increasing and are consequently influencing the design of the building envelope.
‘Resilience’ describes the function and ability of buildings and their facades to to recover from or adjust
easily to change. “Resilience” addresses the impacts of climate change and globalization and of safety and security requirements on the building envelope. The first edition of the Detmold Conference Week 2017 connects education and research, scholars and professionals in different events and formats: a master workshop and two conferences will discuss the approaches of resilient design and construction for buildings and facades.
The direct way to specific stresses forced by water, wind, fire, explosion or earthquake but also in an indirect way seen as a general ability of adaptivity to different changes will be discussed at the facade2017 conference on Friday 24th November 2017 from different academic and professional perspectives.
The 1st RMB Conference on Thursday 23rd November 2017 is organized by the consortium of the ERASMUS+
project “RMB: Reuse of Modernist Buildings. Design Tools for Sustainable Transformations”. There representatives of the consortium as well as international guest will debate in particular issues of Resilience of Modern Movement Buildings and Neighborhoods. During the conference we will discuss new design and educational concepts for the reuse of modern postwar buildings for housing and other purposes – resilience through reuse. Scholars, PhD and master students present and discuss selected papers and posters
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