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Dissertations / Theses on the topic 'Wear rings'

Author: Grafiati

Published: 28 May 2022

Last updated: 30 July 2025

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1

Skytte, af Sätra Ulf. "Wear of piston rings in hydrostatic transmissions." Doctoral thesis, KTH, Machine Design (Div.), 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-432.

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<p>This study focuses on the wear of piston rings in a hydraulic radial piston motor. The piston ring has to satisfy increasing demands for reliability and longer service life. It has two contacting surfaces, the face and the flank, and operates under a boundary lubrication state.</p><p>This first part of the project aimed to detect and characterise piston ring wear. Measurement by weighing gives an overall value for wear defined as loss of mass. Two-dimensional form and surface roughness measurements show the distribution of wear on the piston ring face in contact with the cylinder bore and t

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2

Skytte, af Sätra Ulf. "Wear of piston rings in hydrostatic transmissions /." Stockholm : Department of Machine Design, KTH, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-432.

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3

Тарасевич, Юлія Ярославівна, Юлия Ярославовна Тарасевич, Yuliia Yaroslavivna Tarasevych та А. П. Шевченко. "Решение осесимметричной задачи гидроупругости деформируемых щелевых уплотнений". Thesis, Изд-во СумГУ, 2004. http://essuir.sumdu.edu.ua/handle/123456789/23109.

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4

Марцинковський, Володимир Альбінович, Владимир Альбинович Марцинковский, Volodymyr Albinovych Martsynkovskyi та Н. С. Гетьманский. "Исследование динамики упруго опертой стенки плоского дросселирующего канала". Thesis, Изд-во СумГУ, 2004. http://essuir.sumdu.edu.ua/handle/123456789/23056.

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5

Марцинковський, Володимир Альбінович, Владимир Альбинович Марцинковский, Volodymyr Albinovych Martsynkovskyi та Д. А. Фишер. "Радиально-угловые колебания в щелевых уплотнениях с учетом гидромеханичиских сил и моментов". Thesis, Изд-во СумГУ, 2008. http://essuir.sumdu.edu.ua/handle/123456789/20524.

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6

GARCIA, MARCOS B. "Caracteristicas do desgaste de aneis de pistao com diferentes tecnologias de tratamentos superficiais." reponame:Repositório Institucional do IPEN, 2003. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11149.

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Made available in DSpace on 2014-10-09T12:48:54Z (GMT). No. of bitstreams: 0<br>Made available in DSpace on 2014-10-09T13:58:12Z (GMT). No. of bitstreams: 1 09605.pdf: 8733026 bytes, checksum: 49dd6903a91a39b5240ad2d704c956d5 (MD5)<br>Dissertacao (Mestrado)<br>IPEN/D<br>Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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7

Sabbagh, F. "Wear characteristics of cast iron and steel under boundary lubricated conditions : A study of boundary lubricated wear of cast iron piston rings and its relation to their wear under engine conditions, with a comparative wear study on roller bearing steel." Thesis, University of Bradford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381032.

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8

Nadeem, Tariq. "Computer simulation of the steady-state thermodynamic processes and piston ring wear for a multi-stage intercooled reciprocating air compressor." Thesis, Virginia Tech, 1988. http://hdl.handle.net/10919/43257.

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The objectives of this research are the prediction of the thermodynamic behavior of a multi-stage intercooled reciprocating compressor and its progressive loss of performance due to leakage. A theoretical model is developed to simulate the thermodynamics of the compressor system and the lubricating condition and wear of the piston ring pack for a multi-stage intercooled reciprocating compressor. A first law of thermodynamics approach is used to determine the thermodynamic properties of the gas inside the cylinders, the intercoolers and the inlet and discharge manifold. The compressor valves ar

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9

Goussakov, Alex, and Alin Dumitru Durac. "Tribological characterisation of turbocharger turbine sealing rings in heavy duty diesel engines." Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-67300.

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This work investigated the wear mechanisms of turbocharger components in heavy duty diesel engines. By understanding the wear mechanisms that are occurring in turbochargers the life time of the turbocharger components can be improved. For better understanding, as to why the components are worn out, an analysis of several turbocharger components and tribological tests were carried out. The contact surfaces between turbocharger and sealing rings were analysed. Surfaces are analysed by several methods, including chemical composition of the surface. Influence of different parameters such as cont

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10

Kassfeldt, Elisabet. "The influence of back-up rings and rubber compressibility on hydraulic cylinder seal performance." Licentiate thesis, Luleå tekniska universitet, Maskinelement, 1985. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26648.

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11

MARQUES, RENNER GUILHERME DA COSTA. "STUDY OF FEASIBILITY IN REPLACING IN A CENTRIFUGAL PUMP THE STATIC WEAR RING BY A FLOATING WEAR RING." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2015. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=26598@1.

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PETRÓLEO BRASILEIRO S. A.<br>Grande parte dos sistemas de bombeamento existentes em refinarias é do tipo centrífuga com rotor em balanço. Alguns desses sistemas, que foram fabricadas antes da década de 80, ainda estão sendo usadas em refinarias no Brasil. Tipicamente estes equipamentos possuem rotores muito flexíveis. Isto ocorre devido ao alto valor da razão entre a distância entre mancais e o diâmetro do eixo e também por causa da substituição de gaxetas, que oferecem rigidez, por selos mecânicos. Como consequência, a resposta dinâmica destes equipamentos é sensível à pequenas variações da f

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12

Filho, Dinecio dos Santos. "Alterações metalúrgicas e topográficas do cilindro de bloco de motor de combustão interna flex-fuel." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/3/3133/tde-09022015-163026/.

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O presente estudo descreve as alterações metalúrgicas e topográficas do cilindro de blocos de motor de combustão interna fabricados em ferro fundido cinzento, após a realização de testes de durabilidade em dinamômetro. O motor testado tem tecnologia Flex-Fuel, e pode ser operado com qualquer proporção de mistura gasolina comum/etanol. Um motor foi testado com combustível etanol e o outro com gasolina comum, buscando-se assim representar duas condições extremas de trabalho em termos de combustível. A pesquisa constituiu-se da revisão bibliográfica e da parte prática que envolveu: a realização d

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13

Bush, Graham Peter. "An investigation into piston ring blowby and its effect on biogas engines." Thesis, De Montfort University, 1986. http://hdl.handle.net/2086/10683.

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This study has investigated the severe corrosion of Biogas engines by the blowby gases. The formation of blowby its composition and flow rate have been measured and simulated. The nature of the piston ring sealing, lubrication and breakdown has been examined. A study of Biogas engines showed that Copper corrosion of the small end and camshaft bearings by HZS gas was the reason for engine failure. H2S is present in all Biogas at a concentration of usually less than 1%, but succeeds in chemical attack despite its good combustion properties, and the expected reaction with the bases present in the

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14

Schoonmaker, Benjamin L. "Clean Indices of Common Rings." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7027.

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Lee and Zhou introduced the clean index of rings in 2004. Motivated by this work, Basnet and Bhattacharyya introduced both the weak clean index of rings and the nil clean index of rings and Cimpean and Danchev introduced the weakly nil clean index of rings. In this work, we calculate each of these indices for the rings ℤ/nℤ and matrix rings with entries in ℤ/nℤ. A generalized index is also introduced.

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15

Akurati, Parthasri, and Karan Kumar. "Development of a 3D Ring Dynamics Model For a Heavy-Duty Piston Ring-Pack." Thesis, Blekinge Tekniska Högskola, Institutionen för maskinteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-21638.

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With the increasing restrictions in emission legislations, the automotive industry aims to improve the efficiency of the lubricating system and to decrease fuel consumption. In the power cylinder unit (PCU), the piston rings are the major contributor to these consumptions. Hence, focus on the dynamic behaviour of the rings to reduce lube oil consumption (LOC) becomes a key factor in thriving towards sustainability. Several studies have been conducted on the piston ring-pack specifically using a 2D ring dynamics approach. This study focuses on developing a 3D ring dynamics model, in the softwar

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16

Diggins, Jonathan. "Computational modelling of weak link SQUID ring circuits." Thesis, University of Sussex, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386508.

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17

Webb, Robert D. "A literature review of slip ring performance and an evaluation of four lubricants in a slip ring wear application." Master's thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-02022010-020203/.

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18

Campanini, Federico. "Weak forms of the Krull-Schmidt theorem and Prüfer rings in distinguished constructions." Doctoral thesis, Università degli studi di Padova, 2019. http://hdl.handle.net/11577/3422693.

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This thesis is divided in two chapters. The first one concerns direct-sum decompositions in additive categories. It is well known that if a module admits a direct-sum decomposition into indecomposable modules with local endomorphism rings, then this decomposition is essentially unique, up to isomorphism and a permutation of the direct summands. However, there are situations in which direct-sum decompositions into indecomposable modules are not essentially unique. Among these cases, particularly interesting are those in which it is possible to find some kind of regularity: direct-sum decomposi

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19

Wei, Xiaomin. "FUNDAMENTAL CHARACTERIZATION OF TRIBOLOGICAL, THERMAL, FLUID DYNAMIC AND WEAR ATTRIBUTES OF CONSUMABLES IN CHEMICAL MECHANICAL PLANARIZATION." Diss., The University of Arizona, 2010. http://hdl.handle.net/10150/195125.

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This dissertation presents several studies relating to fundamental characterization of CMP consumables in planarization processes. These are also evaluated with the purposes of minimizing environmental impact and reducing cost of ownership (COO).The first study is conducted to obtain the retaining ring wear rate in a typical ILD CMP process and is specifically intended to investigate the effect of retaining ring materials and slot designs during the CMP process. The results show that retaining ring materials have effect on the COF, pad temperature and retaining ring wear rate, while retaining

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20

Stalvey, Harrison. "Weak Primary Decomposition of Modules Over a Commutative Ring." Digital Archive @ GSU, 2010. http://digitalarchive.gsu.edu/math_theses/84.

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This paper presents the theory of weak primary decomposition of modules over a commutative ring. A generalization of the classic well-known theory of primary decomposition, weak primary decomposition is a consequence of the notions of weakly associated prime ideals and nearly nilpotent elements, which were introduced by N. Bourbaki. We begin by discussing basic facts about classic primary decomposition. Then we prove the results on weak primary decomposition, which are parallel to the classic case. Lastly, we define and generalize the Compatibility property of primary decomposition.

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21

Zhou, Qing. "Friction and wear of piston ring : cylinder liner contact in a large marine diesel engine." Thesis, Brunel University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393177.

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22

Papadopoulos, Panagiotis. "Investigation of fundamental wear mechanisms at the piston ring/cylinder wall interface in internal combustion engines." Thesis, University of Leeds, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.435922.

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23

Spero, Christos. "The influence of coal properties on the grinding and wear characteristics of ring-and-ball pulverisers." Thesis, Queensland University of Technology, 1989. https://eprints.qut.edu.au/36451/1/36451_Spero_1989.pdf.

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This research project was broadly aimed at defining the influence of coal properties on the grinding and wear characteristics of ring-and-ball pulverisers. Work undertaken included a critical review of relevant literature concerned with the grindability and abrasion characteristics of coal, the characterisation of coals used in relation to the pulverisers considered, and correlation of these properties with actual pulveriser grinding performance and wear life. Results presented demonstrate the applicability of several model tests to the quantification of 'hard to grind' material and t

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24

Armand, Marc Andre. "Contributions to the decoding of linear codes over a Galois ring." Thesis, University of Bristol, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297851.

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25

Loveček, Libor. "Laboratorní metody testování kluzných ložisek spalovacích motorů." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-377518.

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The aim of this work is to set similar tribological conditions at different levels of testing and to determine the resultant parameters, which can be compared with a special testing device for testing of journal bearings.

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26

Söderfjäll, Markus. "Simulation of twin land oil control ring in heavy duty diesel engines." Licentiate thesis, Luleå tekniska universitet, Maskinelement, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-17909.

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With today’s striving towards reduction of fuel consumption it is moreimportant than ever to understand how different components in theinternal combustion engine function. There is a need for tools that canbe used to investigate and predict the result of specific design changesmade on the components. In this work, the mechanics and the tribologyof the power cylinder unit and more specifically the operation of thetwin land oil control ring (TLOCR) is investigated. In heavy duty dieselengines (HDDE), TLOCR are typically used. The TLOCR plays a veryimportant role in the engine since it is suppose

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27

Wassborg, Pär. "Tribological evaluation of the contact between upper compression ring and cylinder liner with different surface coatings." Thesis, Karlstads universitet, Institutionen för ingenjörsvetenskap och fysik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-45454.

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The constant pursuit in the automotive industry to increase the engines performance, new solutions are always developed and tested to reduce the friction and increase the efficiency in the engine. One component that contributes to friction losses is the piston ring pack where the top compression stands for up to 40 %. This master thesis collaborated with Scania’s material science department Basic engine and covers the friction and wear of four different materials on the cylinder liner surface against the top compression ring.The four tested materials were grey cast iron with different honing q

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28

Martini, Lorenzo. "Local coherence of hearts in the derived category of a commutative ring." Doctoral thesis, Università degli studi di Trento, 2022. http://hdl.handle.net/11572/354322.

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Approximation theory is a fundamental tool in order to study the representation theory of a ring R. Roughly speaking, it consists in determining suitable additive or abelian subcategories of the whole module category Mod-R with nice enough functorial properties. For example, torsion theory is a well suited incarnation of approximation theory. Of course, such an idea has been generalised to the additive setting itself, so that both Mod-R and other interesting categories related with R may be linked functorially. By the seminal work of Beilinson, Bernstein and Deligne (1982), the derived categor

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29

Masur, Oliver [Verfasser], and Denis [Akademischer Betreuer] Usvyat. "A fragment-based embedded approach for periodic systems and enhanced weak-pair treatment of molecular LCCSD, both based on direct-local-ring-CCD / Oliver Masur ; Betreuer: Denis Usvyat." Regensburg : Universitätsbibliothek Regensburg, 2016. http://d-nb.info/1116080214/34.

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30

Izquierdo, Diego. "Dualité et principe local-global sur les corps de fonctions." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS345/document.

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Dans cette thèse, nous nous intéressons à l'arithmétique de certains corps de fonctions. Nous cherchons à établir dans un premier temps des théorèmes de dualité arithmétique sur ces corps, pour les appliquer ensuite à l'étude des points rationnels sur certaines variétés algébriques. Dans les trois premiers chapitres, nous travaillons sur le corps des fonctions d'une courbe sur un corps local supérieur (comme Qp, Qp((t)), C((t)) ou C((t))((u))). Dans le premier chapitre, nous établissons sur un tel corps des théorèmes de dualité arithmétique « à la Poitou-Tate » pour les modules finis, les tore

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31

PANDEY, SHAILESH MANI. "Wear Behaviour of Piston Ring Coatings." Thesis, 2013. http://dspace.dtu.ac.in:8080/jspui/handle/repository/14252.

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The functions of a piston ring are to seal off the combustion pressure, to distribute and control the oil, to transfer heat and to stabilize the piston. Most piston rings and metallic sealing rings for modern application require some form of coating, where running conditions are severe to minimise abrasion and corrosion. The piston ring coating improves the life of engine as well as fuel efficiency. In this study, three type of piston coating processes were investigated: Plasma Arc Spray, Hard Chrome Plating & Gas Nitriding. Plates with similar composition as the piston ring material wer

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32

Wernelind, Lucas. "Calibration of wear and friction models for a Heavy-Duty Piston Ring pack." Thesis, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-80307.

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33

Huang, Hung-Wen, and 黃泓文. "The Study of Wear of Graphite Brushes with Different Concentrations of Copper Slid Against Copper Ring." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/9ccvux.

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碩士<br>國立高雄應用科技大學<br>機械與精密工程研究所<br>102<br>The main objects of this article is to explore the different amounts of copper graphite brushes after the first brass ring friction ( rear ) of the surface morphology , elemental composition and the relative change in the relationship between the surface energy, and changes in their composition and morphology of wear debris of analysis on the pin-on-disc wear testing machine modified a clamping feed mechanism to reduce the impact of external factors, this mechanism design disassembly time is short, so that the experimental material remains stable in the

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34

Dung-Lin, Chen, and 陳東林. "Temperature measurement and the wear rate study of friction interface of graphite-carbon brush and copper ring." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/55501660956311131633.

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碩士<br>國立高雄應用科技大學<br>機械與精密工程研究所<br>98<br>Since relative motion of friction surface would generate the heat, the temperature will rise by accumulative heat in friction process and result in change on appearance of friction surface. These factors make friction phenomenon complicated and hard to predict. Meanwhile, the measurement of temperature on friction surface is not easy. The research adopted the self-designed graphite-carbon brush sensor to measure the temperature on friction surface and also the wear rate under fixed loading and rotation speed to analyze the relationship among friction c

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35

Nsayi, Jissy Nsonde. "Variants of P-frames and associated rings." Thesis, 2015. http://hdl.handle.net/10500/21795.

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We study variants of P-frames and associated rings, which can be viewed as natural generalizations of the classical variants of P-spaces and associated rings. To be more precise, we de ne quasi m-rings to be those rings in which every prime d-ideal is either maximal or minimal. For a completely regular frame L, if the ring RL of real-valued continuous functions of L is a quasi m-ring, we say L is a quasi cozero complemented frame. These frames are less restricted than the cozero complemented frames. Using these frames we study some properties of what are called quasi m-spaces, and observ

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36

Siang, Yin-Ze, and 向胤澤. "A Strong Designated-Verifier Weak Linkable Ring Signature Scheme for Strongest Signer Anonymity." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/08902902842695171158.

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碩士<br>淡江大學<br>資訊工程學系碩士班<br>99<br>For the anonymous applications, Chen et al. proposed a designated-verifier linkable ring signature scheme with “one-out-of-n” signer anonymity, where n is the number of ring members. In their scheme, the computational cost of each designated-verifier linkable ring signature is proportional to n. The maximum signer anonymity should be one-out-of-maximum anonymity that each one is hidden among all possible users, so n should be the total number of users. Due to the computational cost, Chen et al.’s scheme is an inefficient solution when n is very large. Moreo

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37

Lin, Hung-wen, and 林鴻文. "The Effect of the Surface Property of Cylinder Wall and the Geometrical Shape of Piston Ring on Engine Wear Resistance and Performance." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/15244685163805869472.

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碩士<br>國立臺灣科技大學<br>機械工程系<br>88<br>Weather the lubrication of engine can be effected by the surface property of cylinder wall and the geometrical shape of piston ring or not has been researched in this study. Here, we try different alternated surface property of cylinder wall combining the geometrical shape of piston ring in order to improve wearing resistance, reduce oil consumption and lower loss rate by blowing. Experiments design by Taguchi parameter method. Firstly, we change the contour of piston ring and the surface roughness of cylinder wall to find out the factors effecting on oil consu

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38

Peng, Guo-Hsuan. "Characteristic Analysis and Pulse Compression of the Weak-Resonat-Cavity Fabry-Perot Laser Diode Mode-Locked Fiber Ring." 2008. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-2307200818084700.

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39

Nasehpour, Peyman. "Content Algebras and Zero-Divisors." Doctoral thesis, 2011. https://repositorium.ub.uni-osnabrueck.de/handle/urn:nbn:de:gbv:700-201102107989.

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This thesis concerns two topics. The first topic, that is related to the Dedekind-Mertens Lemma, the notion of the so-called content algebra, is discussed in chapter 2. Let $R$ be a commutative ring with identity and $M$ be a unitary $R$-module and $c$ the function from $M$ to the ideals of $R$ defined by $c(x) = \cap \lbrace I \colon I \text{~is an ideal of~} R \text{~and~} x \in IM \rbrace $. $M$ is said to be a \textit{content} $R$-module if $x \in c(x)M $, for all $x \in M$. The $R$-algebra $B$ is called a \textit{content} $R$-algebra, if it is a faithfully flat and content $R$-module and

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40

Zhang, Rui. "The syntheses, NMR and photochromic properties of modified dimethyldihydropyrenes." Thesis, 2007. http://hdl.handle.net/1828/247.

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The cyclopentadienone-fused dihydropyrenes 46 and 47 were synthesized. The internal methyl resonances, the coupling constants, NICS calculations and X-ray results confirmed that the cyclopentadienone displays antiaromatic character resulting in bond localization in the annulene ring consistent with a 4n-pi fused system. The ring current of the dihydropyrene fragment is reduced by fusion of the antiaromatic system by about 80% of that caused by benzene. The syntheses of the methylfulvene fused dihydropyrene 56 and the phenylfulvene fused dihydropyrene 58 have been accomplished. The calculate

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