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Hydrodynamic processes at the water-sediment interface of streambeds

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Book Series: Dissertationsreihe am Institut für Hydromechanik der Universität Karlsruhe / Universität Karlsruhe (TH), Institut für Hydromechanik ISSN: 14394111 ISBN: 9783866442443 Year: Volume: 2008/1 Pages: IV, 153 p. DOI: 10.5445/KSP/1000008267 Language: GERMAN
Publisher: KIT Scientific Publishing
Subject: General and Civil Engineering
Added to DOAB on : 2019-07-30 20:02:00
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Simultaneous 2D pressure and 2D velocity information at the rough water-sediment interface of streambeds were gained by a newly developed measurement setup. In the bed the pressure fluctuations decay exponentially within the first 1-2 equivalent sand roughnesses. Structural findings concerning coherent flow structures are consistent with models originally developed for smooth walls. A significant bed destabilizing flow-pressure pattern was identified for the first time.

Untersuchung zum effizienten Betrieb von Hydraulikzylindern in Konstantdrucksystemen unter Verwendung einer Zwischendruckleitung

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Book Series: Karlsruher Schriftenreihe Fahrzeugsystemtechnik / Institut für Fahrzeugsystemtechnik ISSN: 18696058 ISBN: 9783731502951 Year: Volume: 28 Pages: XXI, 161 p. DOI: 10.5445/KSP/1000043836 Language: GERMAN
Publisher: KIT Scientific Publishing
Subject: Technology (General)
Added to DOAB on : 2019-07-30 20:02:01
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A constant pressure system with discrete pressure potentials is investigated for efficient actuation of hydraulic cylinders. These pressure potentials are created using an intermediate pressure line. Two switch valves can combine high- intermediate- and tank pressure in order to enable multiple pressure potentials at the controlling porportional valve.

Deep Carbon in Earth: Early Career Scientist Contributions to the Deep Carbon Observatory

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889453634 Year: Pages: 221 DOI: 10.3389/978-2-88945-363-4 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Geography --- Chemistry (General) --- Microbiology --- Environmental Sciences
Added to DOAB on : 2018-02-27 16:16:45
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Since its inception, the Deep Carbon Observatory (DCO) has coalesced a multidisciplinary and international group of researchers focused on understanding and quantifying Earth’s deep carbon budget. Carbon is the fourth most abundant element in the universe, and understanding carbon chemistry under a variety of environmental conditions impacts all aspects of planetary sciences, including planet formation, the form and function of planetary interiors, and the origin and diversity of life. DCO recognizes that is integrating and promoting the contributions of early career scientists are integral to the advancement of knowledge regarding the quantities, movements, origins, and forms of Earth’s deep carbon through field, experimental, analytical, and computational research. Early career scientists represent the future of deep carbon science and contribute substantially to ongoing research by implementing innovative ideas, challenging traditional working schemes, and bringing a globally interconnected perspective to the scientific community. This research topic highlights the contributions at the forefront of deep carbon research by DCO Early Career Scientist community. The manuscripts of this Frontiers e-volume bear evidence of the rapid advances in deep carbon science, and highlights the importance of approaching this field from a plethora of different angles integrating disciplines as diverse as mineralogy, geochemistry and microbiology. This integration is fundamental in understanding the movements and transformations of carbon across its deep cycle.

DHA for Optimal Health

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ISBN: 9783038429715 9783038429722 Year: Pages: X, 276 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Psychology
Added to DOAB on : 2018-06-26 16:08:39
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This Special Issue of Nutrients, entitled "DHA for Optimal Health", consists of evidence-based original research or reviews of the scientific literature. Manuscripts focus on the evidence that underpins dietary requirements throughout the lifespan (from in-utero to the elderly) for optimal brain function and/or prevention (or treatment) of disease.

Advanced Hydroinformatic Techniques for the Simulation and Analysis of Water Supply and Distribution Systems

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ISBN: 9783038429531 9783038429548 Year: Pages: VIII, 370 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Environmental Sciences --- Hydraulic Engineering
Added to DOAB on : 2018-07-19 14:00:08
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The overall objective of this Special Issue is to improve knowledge on developing and using advanced simulation tools in water supply and distribution systems. The final aim is to propose a suitable framework supporting insightful hydraulic mechanisms to help the decision-making processes of water utility managers and practitioners. Contributions to this Special Issue, exploring new research avenues on urban hydraulics and hydroinformatics, will be of great value for both Academia and those water utility stakeholders. On top of this, important social benefits are expected from a number of research objectives that ultimately aim to guarantee a regular supply of clean water at the pressure and quality required at the network consumption points. These objectives include a wide spectrum of subjects, such as demand monitoring and forecasting; network sectorisation; innovative tools for water resources management; leakage detection; system maintenance; transient control; and consumer satisfaction assessment, among others.

Chocolate and Health: Friend or Foe?

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889454112 Year: Pages: 77 DOI: 10.3389/978-2-88945-411-2 Language: English
Publisher: Frontiers Media SA
Subject: Allergy and Immunology --- Nutrition and Food Sciences --- Medicine (General)
Added to DOAB on : 2018-11-16 17:17:57
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In the ancient past, cocoa has been appreciated as a high-calorie food to boost energy in soldiers and for its undefined medicinal and mystical properties. During other times, chocolate has been considered as the forbidden “food of God”: a treasure of pleasure for the mind and the soul. The overall perception of the consumer for chocolate was of a “charming” and appealing food with lots of negative aspects related to high sugar content leading to consider chocolate as “junk food” for its “obesigen” calories. Recently, in association with the renewed interest of nutrition science in alternative source of health-promoting foods and ingredients, a large body of research has been conducted to unravel the pro and cons of cocoa in relation to human health. Epidemiological evidences indicate that cocoa consumption helps preventing cardiovascular disease for its high content in bioactive flavonoids. Clinical trials show that chocolate consumption might improve vascular function, decreasing platelet aggregation and display an antioxidant and anti-inflammatory effect. The putative protective action of cocoa seems to be multi-factorial and involving different aspects of vascular, antioxidant and endothelial function. However, the mechanism(s) that account for the benefits of cocoa it is still unclear.The aim of this Research Topic is therefore to provide the reader with an objective picture of the state of art on the association between cocoa and health, mainly through the evidences of human trials; overwhelmingly considered the golden standard for nutritional science. The Research Topic will cover the analysis of the manufacturing processes of the chocolate and the antioxidant effects in humans as well as the majority of the putative health effects of chocolate and cocoa, such as anti-inflammatory properties, effect on immunity, platelet aggregation, blood pressure, endothelial function and cognitive behavior. Unraveling the functional properties of cocoa will help to understand if the 'food of God' is a primordial gift for the health of mankind.

Less and Non-invasive Hemodynamic Monitoring Techniques

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889456857 Year: Pages: 66 DOI: 10.3389/978-2-88945-685-7 Language: English
Publisher: Frontiers Media SA
Subject: Medicine (General)
Added to DOAB on : 2019-01-23 14:53:43
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In the perioperative setting and in intensive care medicine, early and effective hemodynamic management including fluid therapy and administration of vasoactive drugs to maintain vital organ perfusion and oxygen delivery is mandatory. Understanding the different approaches in the management of critically ill patients during the resuscitation and further management is essential to initiate adequate context- and time-specific interventions. Optimization of hemodynamic variables to achieve a balance between organ oxygen delivery and consumption is a cornerstone. In general, cardiac output (i.e., the blood flow) is considered a major determinant of oxygen supply and thus its monitoring is regarded helpful. However, indicators of oxygen requirements are equally necessary to assess adequacy of oxygen supply. Currently, more and more less or even totally non-invasive monitoring systems have been developed and clinically introduced, but they require validation in particular clinical settings. Cardiac output monitors and surrogates of organ oxygenation only enable to adequately guide management, as patient’s outcome is determined by acquisition and interpretation of accurate measurements, and finally, suitable management decisions.This Research Topic focuses on the currently available techniques, especially the less and non-invasive ones, in the field of hemodynamic monitoring in the perioperative setting and in critically ill patients while summarizing their advantages and limitations.

High accuracy determination of skin friction differences in an air channel flow based on pressure drop measurements

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Book Series: Schriftenreihe des Instituts für Strömungsmechanik, Karlsruher Institut für Technologie ISSN: 21998868 ISBN: 9783731505020 Year: Volume: 2 Pages: VIII, 222 p. DOI: 10.5445/KSP/1000053260 Language: ENGLISH
Publisher: KIT Scientific Publishing
Subject: Technology (General)
Added to DOAB on : 2019-07-30 20:01:58
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The present work delivers a versatile, accurate and reliable wind tunnel facility that is particularly developed to test different flow control techniques for drag reduction in precisely adjustable test conditions. Skin friction changes of 0.4% are resolved, which is comparable to the most accurate reported studies in liquids. this high accuracy is verified through a comprehensive uncertainty analysis. Subsequently, various passive and active flow control strategies are investigated.

Energieeffizienz von Konstantdrucksystemen mit sekundärgeregelten Antrieben beim Einsatz in mobilen Arbeitsmaschinen

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Book Series: Karlsruher Schriftenreihe Fahrzeugsystemtechnik / Institut für Fahrzeugsystemtechnik ISSN: 18696058 ISBN: 9783731503774 Year: Volume: 35 Pages: XXV, 163 p. DOI: 10.5445/KSP/1000047003 Language: GERMAN
Publisher: KIT Scientific Publishing
Subject: Technology (General)
Added to DOAB on : 2019-07-30 20:01:59
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Within this work, it is investigated under which conditions constant pressure systems with secondary controlled drives may be an energetic efficient and cost effective alternative to established mobile hydraulic circuit configurations. For this purpose, a methodology is introduced to evaluate chances and risks at employment of this technology in mobile machines. A demonstrator with three secondary controlled variable displacement drives is developed to confirm the results of the methodology.

Investigation of flow and pressure characteristics around pyramidal buildings

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Book Series: Dissertationsreihe am Institut für Hydromechanik der Universität Karlsruhe (TH) ISSN: 14394111 ISBN: 3937300724 Year: Volume: 2005,3 Pages: XVI, 138 p. DOI: 10.5445/KSP/1000003455 Language: ENGLISH
Publisher: KIT Scientific Publishing
Subject: General and Civil Engineering
Added to DOAB on : 2019-07-30 20:02:00
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Pyramidal buildings are undergoing a renaissance in todays architectural design due to their attractive mystery that has fascinated many architects. From an aerodynamic engineering point of view, structural buildings with the shape of a pyramid have their own interesting and particular aerodynamic characteristics as compared to other usual structural buildings (i.e. cuboidal).However, despite its distinct aerodynamic characteristics compared to other usual structural buildings, the flow and pressure characteristics around pyramidal structures have not yet been investigated completely. Very limited studies about pyramidal buildings can be found in the literature.Consequently, the technical layout with respect to wind load assumption of pyramidal buildings are usually not listed in standard tables which underlines the need of systematic investigations for pyramidal structures.In this study, pyramids with a wide range of base angle variation (theta = 30°, 40°, 45°, 50°, 55°, 60°, 70°) have been investigated intensively through a detailed and accurate laboratory experiments at the Laboratory of Building- and Environmental Aerodynamics, Institute for Hydromechanics, at the University of Karlsruhe. The flow measurements were performed using a 2-D Laser Doppler anemometry (LDA) and The pressure measurements were carried out using a standard pressure tapping technique. The present study focuses on the most important parameters affecting the flow and pressure characteristics that include the influence of base angles, the influence of wind directions and the influence of the pyramid heights with respect to a characteristic length. Besides the experimental investigations, numerical investigations with the aid of a software package called FLOVENT were also additionally performed in order to prove, whether experimental and numerical studies deliver the same results.Based on the flow measurement results, this study was able to distinguish the general characteristics of flow around pyramid building when compared to other type of structures (i.e. cuboidal structure). A set of equations to calculate the reattachment length at the leeward side of the pyramid was generated. In addition, an equation to estimate the zero streamline and an area below line as a function of the reattachment length and base angle, respectively, are proposed. These equations will illustrate the recirculation zone at the leeward side of the pyramid.The pressure measurement results show that the three investigated parameters (base angle, wind direction and pyramid height) have an important influence to the pressure characteristics (magnitude of pressure, suction and fluctuation) in the surfaces of the pyramids. For practical purposes, this study was able to provide the typical values of pressure and aerodynamic coefficients for pyramidal buildings that can be used for structural calculations. The values that are given in this study can be used to fill in the gap of the unavailable design values for pyramidal buildings in standard tables.

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