Spelling suggestions: "subject:"dock"" "subject:"rock""
221 |
Investigations Of Spin-Dynamics And Steady-States Under Coherent And Relaxation Processes In Nuclear Magnetic Resonance SpectroscopyKarthik, G 03 1900 (has links)
The existence of bulk magnetism in matter can be attributed to the magnetic properties of the sub-atomic particles that constitute the former. The fact that the origin of these microscopic magnetic moments cannot be related to the existence of microscopic currents became apparent when this assumption predicted completely featureless bulk magnetic properties in contradiction to the observation of various bulk magnetic properties [1]. This microscopic magnetic moment, independent of other motions, hints at the existence of a hitherto unknown degree of freedom that a particle can possess. This property has come to be known as the "spin" of the particle. The atomic nucleus is comprised of the protons and the neutrons which possess a spin each. The composite object- the atomic nucleus is therefore a tiny magnet itself. In the presence of an external bias like a magnetic field, the nucleus therefore evolves like a magnetic moment and attains a characteristic frequency in its evolution called the Larmor frequency given by,
(formula)
where η is the magnetogyric ratio of the particle and B is the applied magnetic field. The existence of a natural frequency presents the possibility of a resonance behaviour in the response of the system when probed with a driving field. This is the basic principle of magnetic resonance, which in the context of the atomic nucleus, was discovered independently by Purcell [2] and Bloch [3].
From its conception, the technique and the associated understanding of the involved phenomena have come a long way. In its original form the technique involved the study of the steady-state response of the nuclear magnetic moment to a driving field. This continuous wave NMR had the basic limitation of exciting resonances in a given sample, serially. In due course of time, this technique was replaced by the Fourier transform NMR (FTNMR) [4]. This technique differed from the continuous wave NMR in its study of the transient response of the system in contrast to the steady-state response in the former. The advantage of this method is the parallel observation of all the resonances present in the system ( within the band-width of the excitation). In addition to the bias created by the external field, other internal molecular fields produce additional bias which in turn produce interesting signatures on the spectrum of the system, which are potential carriers of information about the molecular state. The fact that the spins are not isolated from the molecular environment, produces a striking effect on the ideal spectrum of the system. These effects contain in them, the signatures of the molecular local environment and are hence of immense interest to physicists, chemists and biologists.
|
222 |
資本利得稅的風險承擔和閉鎖效果 / The Risk-taking and lock-in effect of capital gain tax彭湘媛, Peng, Hsiang Yuan Unknown Date (has links)
我國在民國102年復徵證券交易所得稅,其本質屬於資本利得稅,本文欲探究資本利得稅對資產選擇之影響,再進一步將閉鎖效果納入資產選擇模型,討論課稅實現原則下,資本利得稅的稅率對資產選擇的影響。
本文假設兩項資產,分別為無風險性資產與風險性資產,發現在資本利得稅、資本損失可完全扣抵的情況下,政府擔任分散風險的角色,財富的風險性下跌,代表性個人增加風險性資產持有份額。納入閉鎖效果討論課徵資本利得稅下的資產選擇,設立兩期模型,代表性個人分配財富於無風險資產與風險性資產。若要代表性個人在第二期轉換投資組合,則代表性個人將要求新投資組合之報酬高於原資產之報酬加上處分原資產所產生之資本利得稅,而代表性個人可透過改變風險性資產持有比例調整新資產組合之報酬。研究發現,新投資組合的風險性資產持有比例受到原資產之資本利得稅率影響,原資產的稅率越高,則新投資組合的風險性資產持有比例越大,主因稅率越高,閉鎖效果的強度越強,因此若代表性個人要轉換資產的話,可透過增加風險性資產持有比例來增加新投資組合的預期報酬,亦表示代表性個人之風險承擔意願增加。
|
223 |
Att underlätta underhållsarbeten av takplacerade ventilationsmoduler : En konstruktionslösning för att öka säkerhet och användarvänlighet / Facilitating the maintenance work on ceiling mounted ventilation modules : A design solution to improve safety and user friendlinessElg, Anton January 2015 (has links)
Denna rapport behandlar ett produktutvecklingsprojekt i kursen Examensarbete för högskoleingenjörsprogrammet innovationsteknik och design, MSGC12, vid fakulteten för hälsa, natur- och teknikvetenskap vid Karlstads universitet våren 2015. Handledare för projektet har varit universitetsadjunkt Lennart Wihk och examinator för projektet har varit professor Leo de Vin. Arbetet gjordes i uppdrag av Carl-Ola Danielsson för Swegon i Arvika. Uppdraget har haft som mål att effektivisera underplåten för en av Swegons komfortmoduler både konstruktion- och utseendemässigt. Detta gjordes för att användarvänligheten och säkerheten vid underhållsarbeten ska öka samt för att skapa ett mervärde hos produkten. Arbetet resulterade i ett flertal koncept för hur låsningsanordningen till komfortmodulernas underplåt kan utformas. En utvärdering av dessa koncept resulterade sedan i ett grundläggande koncept för hur låsningsanordningen bör utformas. Genom layoutkonstruktionen utvecklades det grundläggande konceptet och resulterade i totalt tre slutkoncept. Slutkoncepten är alla en typ av snabblåsning mellan underplåten och komfortmodulen. På grund av den minskade tid som slutkoncepten medför vid öppning och stängning av underplåten minskar den statiska belastningen på användaren. Slutkoncepten möjliggör öppning och stängning av underplåten med ett enhandsgrepp, vilket minskar risken för olyckor vid underhållsarbeten av komfortmodulerna. Det finns utrymme för vidarutveckling av slutkoncepten i form av konstruktionsförbättringar, materialval samt fastmonteringsanordning i underplåt och komfortmodul. / This report covers a product development project within the course Degree of Bachelor of Science thesis for innovation and design engineer program, MSGC12, at the Faculty of Health, Nature and Engineering Science at Karlstad University in the spring of 2015. Lennart Wihk has been the supervisor of the project and Professor Leo de Vin acted as examiner for the project. The work was commissioned by Carl-Ola Danielsson for the company Swegon in Arvika, Sweden. The project aimed at improving the face plate for one of Swegon’s comfort modules in both construction and appearance. This was done to improve the usability and safety during maintenance work and to create an added value in the product. The work resulted in a number of concepts for how the locking device to the comfort modules face plate can be designed. An evaluation of these concepts later on resulted in a basic concept for how the locking device should be designed. By a further development of the basic concept, a total of three final concepts were developed. All of the final concepts are a type of quick locking positioned between the face plate and the comfort module. Because of the reduced time required in opening and closing the face plate, the static load is reduced on the user. The final concepts enable opening and closing of the face plate with one hand, reducing the risk of accidents during maintenance work of the comfort modules. There is room for further development of the final concepts in terms of design improvements, material choice and the mounting arrangement of the face plate and the comfort module.
|
224 |
Modular Locking System to RBS CabinetAlmqvist, Josefin, Sundelius, Emma January 2013 (has links)
Radio base stations contain equipment which enables the use of cell phones all around the world. ERICSSON is developing these stations and everything connected to the area, such as electronics, software and hardware. In a new project ERICSSON plans to make their hardware modular, to satisfy all their customers around the world even if their preferences differ. The task that was given to us was to develop a modular locking system to the radio base station cabinets.The concept was developed in an integrated working process that focused on a user centered final product. The process included the definition of the problem, preliminary studies of areas which are connected to the problem and a summary of the demands that the customers mediated in a list of requirements. The idea generation generated lots of ideas that later on were developed into different concepts. The concepts were evaluated before the final decision was made together with ERICSSON.The final product is a lifting handle connected to a rod and latch system, which already existed. A new mechanical function was created to make the new handle function with the old system. The locking system is modular and it is possible to choose which way to lock the handle, with a cylinder lock or a padlock. Only one module, the cylinder in the middle, needs to be switched to get the other solution. The other parts are the same; this makes the product modular. The lift handle is an entire new design, developed in the project.
|
225 |
Etude et réalisation de sources laser impulsionnelles en optique intégrée sur verre : application à la génération de supercontinuumCharlet, Bertrand 06 December 2011 (has links) (PDF)
Le développement des sources supercontinuum a engendré des avancées majeures dans de nombreux domaines tels que la spectroscopie, la métrologie ou encore la biologie avec la tomographie optique cohérente. Récemment, l'arrivée des fibres à cristaux photoniques (FCPs) a permis la fabrication de telles sources avec des lasers impulsionnels de pompe moins puissants. Ainsi, de par leur compatibilité avec les fibres optiques, les lasers impulsionnels réalisés en optique intégrée sur verre semblent une alternative intéressante pour la réalisation d'une source supercontinuum intégrée. Notre travail a donc eu pour objectif l'étude et la réalisation d'un laser impulsionnel déclenché par modulation passive des pertes assez puissant et compatible avec les fibres à cristaux photoniques dans le but de générer un supercontinuum. Nous avons alors conçu et fabriqué ce laser constitué d'un guide d'onde amplificateur réalisé par échange d'ions dans un verre dopé au néodyme et d'une cavité Fabry-Perot fermée par un miroir diélectrique en entrée et sans miroir de sortie ce qui permet un couplage direct avec une fibre optique. L'hybridation de l'absorbant saturable sous la forme d'une couche mince d'acétate de cellulose dopée au BDN sur le guide d'onde a permis la génération d'impulsions ayant une puissance crête de (2,8 ± 0,6) kW. La source supercontinuum réalisé avec une FCP pompée par le laser préalablement étudié présente un spectre allant de 440 nm à 1600 nm. Les perspectives de cette étude portent sur le changement de matériau absorbant saturable pour permettre l'émission d'impulsions plus puissantes, ainsi que sur l'intégration monolithique de la FCP pour réaliser un dispositif encore plus compact. Elles portent aussi sur la réalisation de lasers intégrés à modes bloqués utilisant cette technologie. Nous avons démontré sa faisabilité ainsi que son régime de fonctionnement en soliton dissipatif. Des caractérisations préliminaires ont également été effectuées.
|
226 |
Type Systems for Distributed Programs: Components and SessionsDardha, Ornela 19 May 2014 (has links) (PDF)
Modern software systems, in particular distributed ones, are everywhere around us and are at the basis of our everyday activities. Hence, guaranteeing their correctness, consistency and safety is of paramount importance. Their complexity makes the verification of such properties a very challenging task. It is natural to expect that these systems are reliable and above all usable. i) In order to be reliable, compositional models of software systems need to account for consistent dynamic reconfiguration, i.e., changing at runtime the communication patterns of a program. ii) In order to be useful, compositional models of software systems need to account for interaction, which can be seen as communication patterns among components which collaborate together to achieve a common task. The aim of the Ph.D. was to develop powerful techniques based on formal methods for the verification of correctness, consistency and safety properties related to dynamic reconfiguration and communication in complex distributed systems. In particular, static analysis techniques based on types and type systems appeared to be an adequate methodology, considering their success in guaranteeing not only basic safety properties, but also more sophisticated ones like, deadlock or livelock freedom in a concurrent setting. The main contributions of this dissertation are twofold. i) On the components side: we design types and a type system for a concurrent object-oriented calculus to statically ensure consistency of dynamic reconfigurations related to modifications of communication patterns in a program during execution time. ii) On the communication side: we study advanced safety properties related to communication in complex distributed systems like deadlock-freedom, livelock-freedom and progress. Most importantly, we exploit an encoding of types and terms of a typical distributed language, session π-calculus, into the standard typed π-calculus, in order to understand the expressive power of concurrent calculi with structured communication primitives and how they stand with respect to the standard typed concurrent calculi, namely (variants) of typed π-calculus. Then, we show how to derive in the session π-calculus basic properties, like type safety or complex ones, like progress, by encoding.
|
227 |
Contech: a shared memory parallel program analysis frameworkVassenkov, Phillip 13 January 2014 (has links)
We are in the era of multicore machines, where we must exploit thread level parallelism for programs to run better, smarter, faster, and more efficiently. In order to increase instruction level parallelism, processors and compilers perform heavy dataflow analyses between instructions. However, there isn’t much work done in the area of inter-thread dataflow analysis. In order to pave the way and find new ways to conserve resources across a variety of domains (i.e., execution speed, chip die area, power efficiency, and computational throughput), we propose a novel framework, termed Contech, to facilitate the analysis of multithreaded program in terms of its communication and execution patterns. We focus the scope on shared memory programs rather than message passing programs, since it is more difficult to analyze the communication and execution patterns for these programs. Discovering patterns of shared memory programs has the potential to allow general purpose computing machines to turn on or off architectural tricks according to application-specific features. Our design of Contech is modular in nature, so we can glean a large variety of information from an architecturally independent representation of the program under examination.
|
228 |
Father Yorke and the labor movement in San Francisco, 1900-1910Cronin, Bernard Cornelius, January 1943 (has links)
Thesis (Ph. D.)--Catholic University of America, 1943. / Includes bibliographical references (p. 230-234).
|
229 |
Father Yorke and the labor movement in San Francisco, 1900-1910Cronin, Bernard Cornelius, January 1943 (has links)
Thesis (Ph. D.)--Catholic University of America, 1943. / Includes bibliographical references (p. 230-234).
|
230 |
Jailed heroes and kitchen heroines, class, gender and the Medalta Potteries strike in postwar AlbertaLoch-Drake, Cynthia January 2001 (has links) (PDF)
No description available.
|
Page generated in 0.2179 seconds