Videnskabelige standarder, målesystem osv.

Neutron spin echo (NSE) spectroscopy is the highest energy resolution neutron scattering technique available for examining a large area (in time and space) in condensed matter physics. This broad dynamic and spatial range is extensively exploited in the study of a wide range of scientific problems ranging from the dynamics of glasses, polymer melts, complex fluids and microemulsions to the elementary excitations in superfluid 4He and to ferromagnets and spin glasses. This book reviews the current status and future prospects in NSE spectroscopy describing the method, latest instrumentation and also the use of NSE in fundamental, hard- and soft-matter science. It provides first-hand information for researchers working in the fields touched by NSE. In addition, young researchers, PhD students and graduates interested in the method will obtain a comprehensive overview and guidelines to implementing the NSE technique.

Multiphase thermal systems (involving more than one phase or one component) have numerous applications in aerospace, heat-exchanger, transport of contaminants in environmental systems, and energy transport and energy conversion systems. Advances in understanding the behaviour of multiphase thermal systems could lead to higher efficiency energy production systems, improved heat-exchanger design, and safer and enhanced treatment of hazardous waste. But such advances have been greatly hindered by the strong effect of gravitational acceleration on the flow. Depending on the flow orientation and the phase velocities, gravitational forces could significantly alter the flow regime, and hence the pressure-drop and heat-transfer coefficients associated with the flow. A reduced gravity environment (or "e;microgravity"e;), provides an excellent tool to study the flow without the masking effects of gravity. This book presents for the first time a comprehensive coverage of all aspects of two-phase flow behaviour in the virtual absence of gravity.

Built in the late 1800s, the Mullaperiyar dam in Kerala was meant to divert the waters of the Periyar River to the arid areas of Madurai in what is now Tamil Nadu, following a 999-year lease with the British government. Today, though, the engineering marvel has turned into a bone of contention between two states, Kerala and Tamil Nadu, over Tamil Nadu's insistence to increase the dam's height and Kerala's concerns regarding safety. This dispute has led to widespread riots and protests in both the states. In May 2014, the Supreme Court ruled in favour of Tamil Nadu, but the protests and apprehensions regarding a possible dam burst continue. Water Woes, a timely, insightful exploration of the dispute, examines all aspects of the burning issue of livelihood versus safety. Using meticulous research as well as interviews with government officials, technical experts, police personnel and the common people of both states, at times risking his safety, the author brings out the points of view of both sides. He also shows how water wars will become a major issue not just between states, but between countries, in times to come. This book is a must-read to understand the importance of resolving a simmering issue which might explode in the near future.

This book systematically summarizes the accuracy, precision, and repeatability levels of field-based tests applied in soccer. It considers such details as the effectiveness of tests for different age categories and sexes. In this book, the readers will be able to check all the field-based tests conceived for fitness assessment in soccer through a large systematic review made to the literature. In addition a brief characterization of each test and presentation of the concurrent validity and repeatability levels for each test will be provided. Finally, the book contains a general discussion of the implications of the tests for different methodological approaches to training. It will be use to sports scientists and practitioners.

In dem Buch werden die physikalischen Eigenschaften der Gase beschrieben und die unterschiedlichen Messverfahren und Sensorprinzipien zur Analyse von Gasgemischen dargestellt. Die Anwendung von Gassensoren in den unterschiedlichen Applikationen wird anhand praxisnaher Beispiele dargestellt. Diese Anwendungsfälle der messtechnischen Erfassung von Gasen stammen aus vielen Bereichen der Technik, insbesondere der Energietechnik, Lebensmitteltechnik, Verfahrenstechnik, Biotechnik, Sicherheitstechnik, Medizintechnik und der Umwelttechnik. Die Anwendung von Gassensoren in den unterschiedlichen Applikationen wird anhand praxisnaher Beispiele dargestellt.Der InhaltPhysikalische Eigenschaften von GasenGassensorenOptische GasmesstechnikFeuchtemessungDurchflussmesstechnikKalibrierung und QualifizierungStaubmesstechnikGassensoren in AnwendungssystemenDie ZielgruppenEntwickler und Anwender der Gasmesstechnik in Industrie und IngenieurbürosMitarbeiter in Forschungsinstituten, Behörden und PrüfanstaltenStudierende, Dozenten und wissenschaftliche Mitarbeiter an Universitäten und HochschulenDer AutorProf. Dr. Gerhard Wiegleb beschäftigt sich seit 1980 mit der Gasmesstechnik. Als F&E-Leiter war er über 15 Jahre in der Industrie tätig, bevor er 1995 einen Ruf an die FH-Dortmund für Umweltmesstechnik annahm. Seitdem arbeitet er auf dem Gebiet der Miniaturisierung von Gassensoren.

The characteristics of electrical contacts have long attracted the attention of researchers since these contacts are used in every electrical and electronic device. Earlier studies generally considered electrical contacts of large dimensions, having regions of current concentration with diameters substantially larger than the characteristic dimensions of the material: the interatomic distance, the mean free path for electrons, the coherence length in the superconducting state, etc. [110]. The development of microelectronics presented to scientists and engineers the task of studying the characteristics of electrical contacts with ultra-small dimensions. Characteristics of point contacts such as mechanical stability under continuous current loads, the magnitudes of electrical fluctuations, inherent sensitivity in radio devices and nonlinear characteristics in connection with electromagnetic radiation can not be understood and altered in the required way without knowledge of the physical processes occurring in contacts. Until recently it was thought that the electrical conductivity of contacts with direct conductance (without tunneling or semiconducting barriers) obeyed Ohm's law. Nonlinearities of the current-voltage characteristics were explained by joule heating of the metal in the region of the contact. However, studies of the current-voltage characteristics of metallic point contacts at low (liquid helium) temperatures [142] showed that heating effects were negligible in many cases and the nonlinear characteristics under these conditions were observed to take the form of the energy dependent probability of inelastic electron scattering, induced by various mechanisms.

Sloshing causes liquid to fluctuate, making accurate level readings difficult to obtain in dynamic environments. The measurement system described uses a single-tube capacitive sensor to obtain an instantaneous level reading of the fluid surface, thereby accurately determining the fluid quantity in the presence of slosh. A neural network based classification technique has been applied to predict the actual quantity of the fluid contained in a tank under sloshing conditions.  In A neural network approach to fluid quantity measurement in dynamic environments, effects of temperature variations and contamination on the capacitive sensor are discussed, and the authors propose that these effects can also be eliminated with the proposed neural network based classification system. To examine the performance of the classification system, many field trials were carried out on a running vehicle at various tank volume levels that range from 5 L to 50 L. The effectiveness of signal enhancement on the neural network based signal classification system is also investigated. Results obtained from the investigation are compared with traditionally used statistical averaging methods, and proves that the neural network based measurement system can produce highly accurate fluid quantity measurements in a dynamic environment. Although in this case a capacitive sensor was used to demonstrate measurement system this methodology is valid for all types of electronic sensors. The approach demonstrated in A neural network approach to fluid quantity measurement in dynamic environments can be applied to a wide range of fluid quantity measurement applications in the automotive, naval and aviation industries to produce accurate fluid level readings. Students, lecturers, and experts will find the description of current research about accurate fluid level measurementin dynamic environments using neural network approach useful.

The textbook acquaints the reader with the architecture of receivers of analog and digital radio systems, helps to study the stages of designing a modern radio receiver and reveals the reasons and methods for its effective operation in networks for various purposes. Particular attention is paid to the methods of generating and processing signals in the receivers of digital systems with multiple access, which make it possible to provide data transfer rates close to the maximum possible (according to Shannon). As a textbook for students studying methods of optimal signal reception, the book will also be useful to specialists in the field of telecommunications involved in the development of radio receivers. The book shows how the development of theoretical, circuitry and integrated technologies led to the active introduction of algorithmic methods for signal processing changed both the design of receivers and the methods of forming the information flow in free space (MIMO, beamforming). The creation of a global 5G network based on heterogeneous networks puts forward new requirements for the architecture of receivers, which are determined by the requirements to achieve high data rates, low time delays or use in networks with coordinated multipoint transmission and reception (CoMP). To consolidate the knowledge gained, the book includes a complete set of materials for online classes, including questions and answers, a guide to solving problems for each chapter, and computer modeling units of receivers in the MicroCAP environment, based on preliminary calculations.

This book comprises the proceedings of the Conference and Exhibition on Non Destructive Evaluation (NDE 2020). The contents of the volume encompass a vast spectrum from Conventional to Advanced NDE including novel methods, instrumentation, sensors, procedures, and data analytics as applied to all industry segments for quality control, periodic maintenance, life estimation, structural integrity and related areas. This book will be a useful reference for students, researchers and practitioners.

The first NATO Advanced Workshop on Quantum Tunneling of Magnetization (QTM) was organized and co-directed by Bernard Barbara, Leon Gunther, Nicolas Garcia, and Anthony Leggett and was held from June, 27 through July 1, 1994 in Grenoble and Chichilianne, France. These Proceedings include twenty-nine articles that represent the contributions of the participants in the Workshop. Quantum Tunneling of Magnetization is not only interesting for purely academic reasons. It was pointed out in the review article by L. Gunther in the December, 1990 issue of Physics World, that QTM may be destined to play a significant role within the next two decades in limiting the density of information storage in magnetic systems. Recent advances have indicated that this limitation may well be reached even earlier than first predicted. Furthermore, the number of people who have entered the field of study of QTM during these past few years has increased many fi)ld. The time was therefore opportune to hold a Workshop to bring together for the first time the leading researchers of QTM, both theoretical and experimental, so as to discuss the current status of the field. The most controversial issue at the time of the Workshop was how to establish r.eliable criteria for determining whether experimental results do indeed reveal manifestations of QTM. We believe that much progress was made at the Workshop on this issue.

This scarce antiquarian book is a facsimile reprint of the original. Due to its age, it may contain imperfections such as marks, notations, marginalia and flawed pages. Because we believe this work is culturally important, we have made it available as part of our commitment for protecting, preserving, and promoting the world's literature in affordable, high quality, modern editions that are true to the original work.

An assessment of the recent achievements and relative strengths of two developing techniques for characterising surfaces at the nanometer scale: (i) local probe methods, including scanning tunnelling microscopy and its derivatives; and (ii) nanoscale photoemission and absorption spectroscopy for chemical analysis. The keynote lectures were delivered by some of the world's best scientists in the field and some of the topics covered include: (1) The possible application of STM in atomically resolved chemical analysis. (2) The principles of scanning force/friction and scanning near-field optical microscopes. (3) The scanning photoemission electron microscopes built at ELETTRA and SRRC, with a description of synchrotron radiation microscopy. (4) Recent progress in the development of spatially-resolved photoelectron microscopy, especially the use of zone plate photon optics. (5) The present status of non-scanning photoemission microscopy with slow electrons. (6) the BESSY 2 project for a non-scanning photoelectron microscope with electron optics. (7) Spatially-resolved in situ reaction studies of chemical waves and oscillatory phenomena with the UV photoemission microscope.

Micro/nanotribology as a field is concerned with experimental and theoretical investigations of processes ranging from atomic and molecular scales to the microscale, occurring during adhesion, friction, wear, and thin-film lubrication at sliding surfaces. As a field it is truly interdisciplinary, but this confronts the would-be entrant with the difficulty of becoming familiar with the basic theories and applications: the area is not covered in any undergraduate or graduate scientific curriculum. The present work commences with a history of tribology and micro/nanotribology, followed by discussions of instrumentation, basic theories of friction, wear and lubrication on nano- to microscales, and their industrial applications. A variety of research instruments are covered, including a variety of scanning probe microscopes and surface force apparatus. Experimental research and modelling are expertly dealt with, the emphasis throughout being applied aspects.

This handbook comprehensively covers the cutting-edge trends and techniques essential for the integration of nondestructive evaluation (NDE) into the changing face of the modern industrial landscape. In particular, it delves into the marriage of NDE with new techniques in e.g. data mining, cloud computing and autonomous operation, highlighting the potential for cyber-physical controlled production and discussing the myriad possible applications across many different industries.The Handbook of NDE 4.0 centers around the Internet of Things and Industry 4.0 ¿ the next generation of industrial production encompassing all aspects of networking across all industrial areas. It discusses the adaptation of existing NDE techniques to emerging new technological areas, such as 3D printing, via the introduction of cyber systems into the inspection and maintenance processes. In addition, the handbook covers topics such as the management and processing of big data with respect to real-time monitoring of structural integrity and reliable inspection of individual components. Remote NDE to include competence not available on-site will be a potential technique to increase reliability of NDE inspections by integrating additional specialist inputs into the decision process by methods such as telepresence, thereby better leveraging the scarce resources of senior inspectors into industrial inspections at multiple sites.The handbook houses a wealth of essential information to help academics, industry professionals and entrepreneurs navigate through this burgeoning new field. The material in this handbook is presented with the intention of ultimately improving human safety through reliable inspections and dependable maintenance of critical infrastructure, while also enhancing business value through reduced downtime, affordable maintenance, and talent optimization.

This book presents novel applications of nanotechnology for the preservation of artistic and historical artifacts. It explains the scientific principles behind numerous nanomaterials and discusses their applications to different types of common movable and fixed artistic substrates. It starts with an overview of the nano-tools developed over the last three decades, such as dispersions of nanoparticles, micellar solutions, microemulsions and gels. Compared to traditional methods, these new tools have the benefit of considerably less impact on both the operators and the environment. Each chapter is dedicated to a specific type of cultural heritage material (wall and easel paintings, stone, paper, canvas and wood) starting with the main degradation paths and discussing protocols for the application of innovative nanomaterials-based tools for cleaning, consolidation, or deacidification, which represent the majority of the case studies encountered in restoration facilities, workshops and ateliers. The book provides step-by-step descriptions that are meant to support conservators in the application of these novel materials and methods. The aim of the book is to equip end-users and conservators with essential information and knowledge on the availability and applicability of different nano-materials and dispersed systems. While the book's focus is on the practical aspects, interested readers will also find references to the relevant advanced colloid and material science literature.Main audience: Expert conservators, restorers and technical staff at conservation institutes and museums, students at conservation and restoration schools, and scientists who are new to the field of conservation of artistic and historical artifacts.