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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Development of Acoustic Modulation Microscopy

Wang, Tzung-Chi 01 July 2006 (has links)
In this study, we have successfully developed an acoustic modulation microscopy that is based on a laser scanning confocal microscopy and operates in the range of a few tens of kilohertz. The induced submicron oscillation is detected through the combination of differential confocal microscopy and lock-in circuit. In this way, the mechanical properties, such as elasticity and stiffness, can be mapped in a two-dimensional way rapidly.
22

The influence of IPO underpricing and lock-up period coverage on buy and hold return

Wu, Chia-Ping 26 June 2003 (has links)
Why are initial public offerings (IPOs) underpriced? We consider this is a strategy that insiders use to maximize their personal wealth. When a company offers shares in an initial public offering, insiders typically enter into a lock-up restriction which prohibits insiders from selling their shares within a specified period after the IPO. Insiders interested in maximizing their personal wealth will take actions to maximize the lock-up expiration share price rather than the offer price. When the IPOs underprice, the share price will go up during the honeymoon period. The large run-up in the stock price will attracts interest from the media. And the enhanced coverage brings the stock to the attention of more investors. Then the demand for the stock will increase and make the stock price go up. This allows the insiders to sell shares at the lock-up expiration at price higher than he would otherwise be able to obtain. This study examines the relationship among underpricing, coverage and return. We find that stock deposit and the age of a company are positively correlated with underpricing. The electronic-related companies are much more noticeable than underpricing to lead to more coverage. We also find that coverage is positively correlated with return through the lock-up expiration.
23

Impacts of Biofuel Production and Navigation Impediments on Agricultural Transportation and Markets

Ahmedov, Zafarbek 16 December 2013 (has links)
This study investigated the impacts of U.S. biofuel production and barge navigation impediments on agricultural transportation and markets. Both past and future impacts of U.S. biofuel production levels mandated by the Renewable Fuel Standards of the Energy Policy Act of 2005 (RFS1) and the Energy Independence and Security Act of 2007 (RFS2) were examined. Examination of barge navigations impediments included analysis of the impact of lock failure and low water levels on rivers due to drought, on agricultural transportation, and on consumer welfare. All scenarios were simulated using the International Grain Transportation Model, a price endogenous mathematical programming model. The results showed that RFS-associated (RFS1 and RFS2) U.S. corn ethanol production increased the total corn supply and diverted corn from non-ethanol consumption, reduced regional grain transportation volumes, and contributed to a rise in corn prices. The results of the forward-looking scenarios indicated that grain exports and transport volumes were increased. Exports from Gulf ports increased by 41%, while grain movements by rail increased by 60%. Additional investments in the expansion of the grain handling capacities of Gulf ports and the railroad industry are needed in the near future unless a large increase in biofuel production occurs. The results of navigation impediment scenarios indicated that both lock failures and low water levels on rivers adversely affect U.S. grain exports. The Gulf ports were most negatively impacted, relative to Pacific Northwest and Atlantic ports. Truck and barge freight volume declined while rail freight volume increased. Because trucks deliver grain from grain elevators to barge locations, truck volume also decreased in response to the decline in barge volume. The scenarios imposed welfare losses on society with most accruing to consumers, while the barge industry lost $10-154 million in revenue. The low water levels were more expensive than the lock failures. Major rehabilitation of the locks is needed to avoid lock failures and more dredging of the shallow parts of the river system is required because of frequent droughts.
24

Le mouvement ouvrier chinois : de 1919 à 1927 /

Chesneaux, Jean, January 1999 (has links)
Th. État--Paris--EHESS, 1962. / Bibliogr. p. 585-616. Index.
25

Evaluation of Upstream Passage and Associated Movement Patterns of Adult Bigheaded Carp (Hypophthalmichthys nobilis and H. molitrix) at a Gated Dam on the Illinois River

Lubejko, Matthew V. 01 December 2016 (has links)
Invasive bighead carp (Hypophthalmichthys nobilis) and silver carp (H. molitrix), hereafter, bigheaded carp, pose a major threat to the Great Lakes ecosystem as they advance toward Lake Michigan via the Illinois River. However, a series of navigation dams may deter their upstream movement. Starved Rock Lock and Dam (SRLD) is the most downstream gated dam on the Illinois River, therefore presenting the first navigation challenge for upstream migrating bigheaded carp. Before 2015, five acoustic receivers near SRLD detected successful upstream passage of only two of 900 tagged bigheaded carp. I further investigated the permeability of SRLD to bigheaded carp migration as a function of temperature, gage height, and dam operation. In 2015, I added 12 receivers around SRLD and acoustically tagged an additional 118 bigheaded carp downstream of SRLD. I also investigated the timing of bigheaded carp arriving downstream of SRLD using a generalized linear model. The explanatory variables influencing bigheaded carp arrival were average water temperature, average tailwater elevation, and the change in average water temperature. During 2015-2016, acoustic receivers recorded a total of 11 upstream passage events through SRLD, with nine through the dam gates, one through the lock chamber, and one undetermined. Passage through the dam gates occurred most frequently at high water levels when the dam gates were completely out of the water. The probability of upstream migrating bigheaded carp approaching SRLD was positively correlated with rising temperature and high gage. No upstream migrants approached SRLD between mid-September and late March. Overall, dam gates were more susceptible to upstream passage than the lock chamber, and environmental factors accurately predicted the arrival of bigheaded carp at SRLD. Modifying gate use during times of bigheaded carp arrival will likely prevent upstream passage through SRLD and other lock and dam structures.
26

Medição de Impedância Para Monitoramento da Vazão Multifásica Pela Técnica da Correlação

SILVA, Fabiano Gabriel da 29 February 2012 (has links)
Submitted by Eduarda Figueiredo (eduarda.ffigueiredo@ufpe.br) on 2015-03-06T14:22:24Z No. of bitstreams: 2 PPGEE_M_233_FABIANO_GABRIEL_2012.pdf: 6382648 bytes, checksum: 220d3a4caf3edf057e04f2335d6d108f (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) / Made available in DSpace on 2015-03-06T14:22:24Z (GMT). No. of bitstreams: 2 PPGEE_M_233_FABIANO_GABRIEL_2012.pdf: 6382648 bytes, checksum: 220d3a4caf3edf057e04f2335d6d108f (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2012-02-29 / Foi desenvolvido um medidor de impedância elétrica utilizando a técnica de detec ção sí ncrona (lock-in). Essa técnica utiliza um sinal de referência para detectar sinais elétricos na presença de ní veis altos de ruí do, sendo utilizada para medir potenciais elétricos ou correntes elétricas extremamente baixas. Isso ocorre quando se deseja medir condutâncias ou capacitâncias muito pequenas ou muito grandes. Para testar o conceito, o medidor foi implementado e caracterizado utilizando a técnica de instrumenta ção virtual com o aplicativo LabVIEW R. Foram realizadas medi ções experimentais e caracteriza ção do medidor com resistências e capacitâncias padrão. O objetivo do projeto e utilizar esse instrumento na implementa ção de um medidor de vazão multifásica pela técnica da correla ção. Diversas técnicas podem ser usadas para realizar a medi ção da vazão. Contudo, de acordo o ambiente e o tipo de ruído a ser medido, algumas são mais e cientes que outras. Isso acaba influenciando na contabilidade da medição. Escoamentos multifásicos são os que possuem a maior dificuldade de medição por serem compostos por mais de um tipo de ruído (água, óleo, ar etc). A medi cão de vazão está presente em nosso dia a dia na produção e distribuição de petróleo, postos de combustíveis, nas empresas abastecedoras de água e tratamento de esgotos, nas indústrias de bebida, entre outros. Ela e fundamental para o controle de processos e para tarifação. A exemplo da medição fiscal, para arrecadação de impostos.
27

Innovations stratégiques des industries en déclin : l’industrie des disques optiques en face de la technologie de rupture / Strategic answers of industries in decline : the confrontation of the optical disc industry with disruptive technology

Oestreicher, Klaus 21 November 2012 (has links)
L’industrie des réplicateurs des disques optiques est menacée dans son existence et se trouve en face d’un déclin permanent. Son produit cœur, CD et DVD, est remplacé par des services virtuels. L’Internet facilite la dématérialisation de ces produits physiques : Une technologie, qui a créée des formes de consommation différente. Cette recherche par étude de cas présente le cas des firmes européennes de cette industrie et de leurs innovations dans l’effort de fuir la menace de l’obsolescence. Le but de cette dissertation est de trouver une réponse aux questions centrales, « comment » et « pourquoi » les réplicateurs des disques optiques innovent pendant le déclin et si leurs innovations sont efficaces pour faciliter la survie. Les découvertes de cette recherche qualitative sont catégorisées dans plusieurs façons : Elles sont étudiées sous les concepts de la logique conventionnelle vs la logique d’innovation de valeurs, le transilience map et un corps d’autres théories (Kim et al. 2005, Abernathy et al. 1984). Le système des géométries de la stratégie sert comme grille d’analyse des résultats (Keidel. 2010). Le résultat principal résultante est, que si cette industrie ne peut pas survivre dans sa structure présente, la majorité de ses innovations subit un effet de lock-in multiple : Technologie, liaisons au marché et motivation/qualification des managers manquante, qui empêche de renverser la donne majoritairement à n’être qu’incrémental. L’innovation nécessaire en phase du déclin et ici étouffée. / The replication industry of optical discs is threatened in its existence and confronted with permanent decline. Its core product, CD and DVD, is replaced by virtual services. The Internet facilitates the dematerialisation of the physical product: A new technology has shaped a different form of consumption.This research by case study presents the case of European firms of this industry and their innovations in the effort to escape the threat of obsolescence. The objective of this research is to find an answer to the central questions, “how” and “why” the replicators of optical discs innovate during decline and whether their innovations are effective to enable the firms’ survival.The discoveries of this qualitative study are categorised in various ways: They are studied by the concepts of conventional logic vs logic of value innovation, the transilience map and further relevant theories (Kim et al. 2005, Abernathy et al. 1984). The system of geometries of strategy is used as analytical structure (Keidel. 2010). The main result is that this industry cannot survive in its present structure, since the majority of its innovations is subject to the effect of a multiple lock-in: Technology, market linkages and the lack of managerial motivation/qualification are the main reason that this industry’s innovation is by its majority incremental. The necessary innovation during decline is eliminated here.
28

FGSCM: uma abordagem de omissão de lock transacional com granularidade fina na resolução de conflitos / FGSCM: a transactional lock elision approach with fine-grained conflict resolution

Sousa, Gustavo José [UNESP] 30 August 2017 (has links)
Submitted by Gustavo José de Sousa null (gustavo.jo.sousa@gmail.com) on 2017-11-07T18:17:35Z No. of bitstreams: 1 dissertacao.pdf: 1114730 bytes, checksum: 360fec3dffa930a34e0cdc2bb0ff960d (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-11-21T13:38:05Z (GMT) No. of bitstreams: 1 sousa_gj_me_sjrp.pdf: 1114730 bytes, checksum: 360fec3dffa930a34e0cdc2bb0ff960d (MD5) / Made available in DSpace on 2017-11-21T13:38:05Z (GMT). No. of bitstreams: 1 sousa_gj_me_sjrp.pdf: 1114730 bytes, checksum: 360fec3dffa930a34e0cdc2bb0ff960d (MD5) Previous issue date: 2017-08-30 / Omissão de lock é uma técnica onde operações de aquisição e liberação de lock são omitidas (especulação) de forma a permitir que regiões críticas compartilhando um mesmo lock possam executar concorrentemente, permitindo assim se explorar um nível maior de concorrência em programas que utilizam esse método popular de sincronização. Para se manter o princípio de atomicidade, as modificações no estado do programa realizadas pela região crítica são mantidas em um buffer interno e são efetivadas apenas ao fim da mesma. Em caso de inconsistências, diferentes políticas em como proceder são possíveis, o que diferencia as diversas abordagens de omissão de lock encontradas na literatura. Por exemplo, a abordagem original, Speculative Lock Elision (SLE), que é implementada no nível microarquitetural, recorre a adquirir o lock de forma tradicional quando uma especulação falha. Em algumas situações, esta política conservadora acaba por restringir o ganho em desempenho originalmente pretendido por impor um volume de sincronização desnecessário (lemming effect). Uma forma de superar tal limitação é o emprego de omissão de lock transacional (Transactional Lock Elision, em inglês), onde a especulação de regiões críticas se dá por meio de transações e o controle de execução é devolvido ao software em eventos de transações abortadas, o que permite que diferentes estratégias sejam empregadas com o objetivo de permitir execução concorrente mesmo em presença de falha de especulação. Neste contexto, uma das abordagens possíveis é o esquema chamado Software-assisted Conflict Management (SCM), onde um lock auxiliar é utilizado para sincronizar transações abortadas e, assim, manter o lock original livre, permitindo que outras transações prossigam sua execução. No presente trabalho, uma extensão ao SCM é proposta, o esquema Fine-grained Software-assisted Conflict Management (FGSCM), onde múltiplos locks são utilizados para permitir que transações abortadas por conflitos em diferentes regiões de memória possam ser executadas de forma concorrente. O algoritmo proposto foi implementado utilizando a interface RTM da extensão Intel® TSX e experimentos foram realizados em um máquina quadcore, para os quais, em casos com predominância de operações de leitura em memória, observou-se um ganho em desempenho médio de 11% e 36% com relação à abordagem SCM original e ao uso de um spin lock comum, respectivamente. / Lock elision is a technique that omits acquire/release lock operations (speculation) so as to allow critical regions sharing the same lock to run concurrently, which yields a higher level of concurrency explored by programs that use such popular synchronization mechanism. In order to honor atomicity, modifications on the program's state made by the critical regions are kept in an internal buffer and only applied at the end of the speculation. If inconsistency is found, different policies on how to proceed are possible, which make up the several existing approaches found in the literature. As an example, the original one, namely Speculative Lock Elision (SLE), which is implemented at the level of microarchitecture, falls back to acquire the lock in a standard manner when there is speculation error. In some situations, such conservative policy ends up restricting the intended performance gains due to the unnecessary synchronization imposed (lemming effect). A way to address this issue is through Transactional Lock Elision (TLE) techniques, in which speculation of critical regions is done by means of transactions and execution control is passed back to software on abort events, which makes possible the use of different strategies to allow concurrent execution even in presence of speculation error. In this context, one possible approach is called Software-assisted Conflict Management (SCM), where an auxiliary lock is used to serialize aborted transactions and, as such, keep the original one free, so that others may proceed on their execution. The work presented in this document proposes an extension of SCM, called Fine-grained Software-assisted Conflict Management (FGSCM), where multiple auxiliary locks are applied in order to allow transactions aborted due to conflict on different regions of memory to be executed concurrently. The proposed algorithm was implemented by using the RTM interface from Intel®'s TSX extension and experiments were performed on a quadcore machine. On read-dominated workloads, an average performance gain of 11% and 36% was observed against the original SCM and a typical spin lock, respectively.
29

CAE Tool for Evaluation of Park Lock Mechanism in a DCT Transmission / CAE verktyg för utvärdering av parkeringslåsmekanism i en växellåda med dubbla kopplingar

Andersson, Rasmus January 2017 (has links)
A park lock mechanism is a device that is fitted to an automatic transmission on a vehicle. The mechanism lock up the transmission so that no rolling of the vehicle can be done when the vehicle is put in the park position. The aim of this thesis is to develop a method in order the evaluate designs on a Park Lock Mechanism (PLM) that can be found in a dual clutch transmission (DCT). A Computer Aided Engineering (CAE) tool to calculate the output that is required for an evaluation of a park lock mechanism design will be created. The CAE tool shall calculate static, dynamic, and snap torque on a ratchet wheel in a gradient, with or without a trailer, also the minimum and maximum coefficient of friction between the pawl and cone, pull out force, the maximum amount of rollback, torque needed from the return spring, preload force from actuator spring, and engagement speed. The CAE tool created uses an Excel Visual Basics for Applications (VBA) workbook for all calculations. The tool allows the user to choose different vehicles with the required specification to evaluate the values for that PLM. The CAE tool will save time and cost if lots of different PLM’s are going to be designed. The CAE tool has potential for future work when more calculations can be added that can be in use for the evaluation the PLM. The CAE tool developed by the master thesis student calculates all the required values for evaluation of a PLM design, executed in a fast, efficient, and easy to use program.
30

Studie plavebního stupně Přelouč II / Feasibility study of the shipping channel Přelouč II

Suchomelová, Aneta January 2019 (has links)
The aim of this thesis is to make more detailed disposition solution of the variant C.2 of shipping channel Přelouč II from the possible variants provided by ŘVC CR. The solution contains detailed technical documentation of the lock chamber. The study is divided into several parts, including an engineering report, hydrotechnical calculations, project documentation of the shipping channel and lock chamber and the photographic docu-mentation of the locality.

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