Dissertations / Theses: 'Bond characteristic'

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Weiland, Silvio, and Manfred Curbach. "Interaktion gemischter Bewehrungen bei der Verstärkung von Stahlbeton mit textilbewehrtem Beton." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1244051366655-25294.

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Textile Bewehrungen stellen eine hervorragende Alternative zu bisherigen Verstärkungsmethoden dar. Die Wirksamkeit von Textilbetonverstärkungen konnte bereits eindrucksvoll nachgewiesen werden. Um sowohl die vorhandene Bausubstanz, als auch die Verstärkung optimal auszulasten, ist es erforderlich, das Zusammenwirken beider Bewehrungsarten unter Berücksichtigung der unterschiedlichen Verbundeigenschaften zu beschreiben. In diesem Beitrag wird das gemeinsamen Tragverhalten von Betonstahl und textiler Bewehrung eingehend erläutert. Zur Veranschaulichung wird daher vor allem die Verbundtragwirkung und deren Einfluss auf gerissene Zugglieder genauer untersucht.

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Yu, Zhenmin. "Relative bond characteristics of epoxy-coated reinforcement." Thesis, University of Leeds, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277400.

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Moneta, Fabio. "Measuring Bond Mutual Fund Performance with Portfolio Characteristics." Thesis, Boston College, 2009. http://hdl.handle.net/2345/2466.

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Thesis advisor: Pierluigi Balduzzi
Employing a novel data set of portfolio weights from 1997 to 2006, the performance of taxable bond mutual funds is studied. The timing ability of fund managers is examined considering different asset allocation choices such as asset class, credit quality allocation, and portfolio maturity decisions. I show that active managers engage in strategies of rotating their portfolios across fixed-income sectors and bond characteristics. Some bond funds exhibit successful timing ability by adopting these strategies. Comparing fund returns plus expenses and transaction costs with the returns of a portfolio that is invested in the previously disclosed holdings, I document that active managers exhibit some ability to select securities that deliver better returns than the securities in the indices. In particular, on average, active managers generate gross returns of 1% per annum over the benchmark portfolio constructed using past holdings
Thesis (PhD) — Boston College, 2009
Submitted to: Boston College. Carroll School of Management
Discipline: Finance

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Seaton, Alexander Miles. "Bond strength performance characteristics of brick-mortar interfaces." Thesis, Sheffield Hallam University, 2004. http://shura.shu.ac.uk/20339/.

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This work uses a direct tensile test approach, developed in-house, to measure the bond strength of brick-mortar interfaces. The thesis postulates that direct tensile bond strength values can be used as a means of assessing compatibility of brick and mortar properties which directly influence the structural and durability performance of brickwork. The work identifies that direct forms of tensile testing are suited for comparative research more readily than flexural testing techniques, which induce inherent variability to the test system due to sample format and by application of the associated flexural bending theory. It is maintained that flexural bending tests reflect parameters which influence disproportionately the compressive strength of the mortar and the joint periphery. The work uses traditional volume ratios for mortars, proportioned to a constant mass of sand, to identify the effect that discrete changes in cement and lime content have upon bond strength performance of the mortar. The results show that cement content of mortar has no significant influence on bond strength, provided that the combined proportion of cement and lime maintain a 1:3 ratio by volume with the sand. Furthermore, it has been shown that the volume of the mix water should match the volume of cementitious material, in order to achieve suitable workability. The work produces a bond strength development curve for samples aged between 5-minutes and 2-years of age and concludes that bond strength does not develop in the same manner to compressive strength and that bond strength may decline post 28-days. Samples up to 2-years in age can demonstrate up to 40-percent loss of bond due to the effects of sustained drying shrinkage. Consequently the work questions the value of using 28-day strength tests as a means of predicting future bond strength performance. It is identified that the controlling parameter which effects bond strength development is the removal of the excess mix water from the mortar by brick suction forces. The work examines unit water absorption characteristics and identifies that the initial rate of suction test is not sufficiently representative of a unit's ability to remove water from a retentive mortar bed. In response a unique method, which measures the continuous water uptake of the brick bed-face is presented. The resulting water absorption profile identifies the rate of change of flow and the resulting force function, with which water is potentially extracted from the retentive mortar bed. Results show that a good correlation between a unit's suction force and bond strength can be attained. It is presented that initial bond strength is developed by volumetric plastic shrinkage of the mortar bed, induced by rapid removal of the excess mix water by brick background suction, which generates a mechanical lateral gripping action to the undulations of the brick bed-face.

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Jacques, Eric. "Characteristics of Reinforced Concrete Bond at High Strain Rates." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34966.

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Despite the on-going intensity of research in the field of protective structural design, one topic that has been largely ignored in the literature is the effect of high strain rates on the bond between reinforcing steel and the surrounding concrete. Therefore, a comprehensive research program was undertaken to establish the effect of high strain rates on reinforced concrete bond. The experimental research consisted of the construction and testing of fourteen flexural beam-end bond specimens and twenty-five lap-spliced reinforced concrete beams. The physical and material properties of the specimens were selected based on a range of design parameters known to significantly influence bond strength. In order to establish a baseline for comparison, approximately half of the total number of specimens were subjected to static testing, while the remainder were subjected to dynamic loading generated using a shock tube. The strain rates generated using the shock tube were consistent with those obtained for mid- and far-field explosive detonation. Results of the beam-end and lap splice beam tests showed that the flexural behaviour of reinforced concrete was significantly stronger and stiffer when subjected to dynamic loading. Furthermore, the high strain rate bond strength was always greater than the corresponding low strain rate values, yielding an average dynamic increase factor (DIF) applied to ultimate bond strength of 1.28. Analysis of the low and high strain rate test results led to the development of empirical expressions describing the observed strain rate sensitivity of reinforced concrete bond for spliced and developed bars with and without transverse reinforcement. The predictive accuracy of the proposed DIF expressions was assessed against the experimental results and data from the literature. It was found that the dynamic bond strength of reinforced concrete can be predicted with reasonably good accuracy and that the proposed DIF expressions can be used for analysis and design of protective structures. An analytical method was also developed to predict the flexural load-deformation behaviour of reinforced concrete members containing tension lap splices. The analysis incorporated the effect of reinforcement slip through the use of pseudo-material stress-strain relationships, in addition to giving consideration to the effect of high strain rates on bond-slip characteristics and on the material properties of concrete and steel. A comparison of the analytical predictions with experimental data demonstrated that the proposed analysis technique can reasonably predict the flexural response of beams with tension lap splices. The results also demonstrated that the model is equally applicable for use at low- and high-strain rates, such as those generated during blast and impact.

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Kerschnitzki, Michael. "Bone material characteristics influenced by osteocytes." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2012. http://dx.doi.org/10.18452/16479.

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In dieser Doktorarbeit wird die Hypothese geprüft, ob Osteozyten einen direkten Einfluss auf die Knocheneigenschaften in ihrer unmittelbaren Umgebung haben. Der zentrale Experimentieransatz ist dabei die Korrelation der Organisation des Osteozytennetzwerks mit den Mineraleigenschaften des Knochens auf der Submikrometerebene. Es wird gezeigt, dass bereits die anfängliche Ausrichtung der Osteoblasten entscheidend für die Synthese von hoch ausgerichtetem Knochenmaterial ist. Die dabei entstehenden Osteozytennetzwerke sind so organisiert, dass die Osteozyten und ihre Zellfortsätze jeweils einen möglichst kleinen Abstand zum Knochenmineral haben. Deshalb wird vermutet, dass genau diese Netzwerkorganisation mitentscheidend ist, wie gut die Zellen das Mineral in ih-rer Umgebung beeinflussen können. Messungen der Knochenmineraleigenschaften auf Submikrometerebene mit Röntgenkleinwinkelstreuung bestätigen diese Vermutung. Dabei wird deutlich, dass Knochenmaterial in der Nähe der Osteozyten durch andere Mineraleigenschaften geprägt ist. Um zu klären, wie Osteozyten Mineral in ihrer direkten Umgebung verändern können, werden Mechanismen der passiven Mineralherauslösung aus der mineralisierten Oberfläche des Osteozytennetzwerks untersucht. Es wird gezeigt, dass kalziumarme ionische Lösungen unter physiologischen Bedingungen große Mengen von Kalzium-Ionen aus dem Knochen lösen und diese dann durch die Osteozytennetzwerkstrukturen diffundieren können. Zum Abschluss wurde medullärer Knochen von Hühnern als ein Modellsystem für rasanten Knochenumbau untersucht. Dieser spezielle Knochentyp dient den Hennen als labiles Kalziumreservoir und ermöglicht dadurch die tägliche Eierschalenproduktion. Experimente am medullären Knochen-material zeigen insbesondere die Bedeutung von weniger stabilen Mineralstrukturen die benötigt werden um den Knochen an den schnellen, sich wiederholenden Knochenauf- sowie Abbau optimal anzupassen.
This thesis aims to test the hypothesis whether osteocytes have a direct influence on bone material properties in their vicinity. In this regard, the concomitant ana-lysis of osteocyte network organization and bone ultrastructural properties on the submicron level is the central approach to answer this question. In this work, it is shown that already initial cell-cell alignment during the process of bone formation is crucial for the synthesis of highly organized bone. Furthermore it is proposed that the occurrence of highly ordered osteocyte networks visualized with confocal laser scanning microscopy (CLSM) has a strong impact on the ability of osteocytes to directly influence bone material properties. These highly organized networks are another consequence of initial cell-cell alignment and are found to be arranged such as to feature short mineral cell distances. Examination of sub-micron mineral properties with scanning small angle x-ray scattering (sSAXS) shows that bone material in the direct vicinity of osteocytes and their cell proc-esses shows different mineral properties compared to bone further away in the depth of the tissue. Moreover, mechanisms of passive mineral extraction from the mineralized surface of the osteocyte network, due to the treatment with calcium poor ionic solutions, are investigated. It is shown that this chemical process occurring under physiological conditions leads not only to the dissolution of considerable amounts of calcium, but also to efficient diffusion of these ions through the osteocyte network structures. Finally, medullary bone which is intended as a labile calcium source for daily egg shell formation in hens is used as a model system for rapid bone turnover rates. This bone type in particular indicates the importance of uniquely adapted, less stable mineral structures to fit the requirements for rapid bone resorption as well as reformation.

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Wang, X., S. Dong, Ashraf F. Ashour, S. Ding, and B. Han. "Bond behaviors between nano-engineered concrete and steel bars." Elsevier, 2021. http://hdl.handle.net/10454/18564.

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Yes
This paper investigated the bond characteristics between eight types of nanofillers modified reactive powder concrete (RPC) and plain steel bars, aiming to explore the modifying mechanisms and establish a bond-slip relationship model for nanofillers modified RPC and steel bar interface. The experimental results indicated that the incorporation of nanofillers can increase the bond strength and reduce the slip between RPC and plain steel bars. It was shown that a 2.15 MPa/20.5% of absolute/relative increase in cracking bond strength, a 1.25 MPa/10.3% of absolute/relative increase in ultimate bond strength, a 2.35 MPa/22.4% of absolute/relative increase in residual bond strength, a 0.592 mm/56.5% of absolute/relative reduction in ultimate bond slip, and a 1.779 mm/52.1% of absolute/relative reduction in residual bond slip were the best achieved due to the addition of various nanofillers. The enhancement of nanofillers on RPC-steel bar interface has been mainly attributed to RPC microstructure improvement, optimization of intrinsic compositions, and elimination of defects in the interface, especially the underside near steel bar, due to the nano-core effect of nanofillers enriched in the interface. In addition, the bond-slip relationship of nanofillers modified RPC-steel bar interface can be accurately described by the proposed model considering an initial branch.
The authors would like to thank the funding offered by the National Science Foundation of China (51978127 and 51908103), and the Fundamental Research Funds for the Central Universities (DUT21RC(3)039).
The full-text of this article will be released for public view at the end of the publisher embargo on 22 Jul 2022.

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Voide, Romain. "Functional phenotyping of bone : a hierarchical assessment of bone failure characteristics." Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17524.

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Lee, Ho-Rim. "Comparative study of bond characteristics between titanium-titanium alloy and ceramic." [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=972776354.

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Balazadeh, Minouei Mani. "Finite element analysis of bond characteristics at the FRP-concrete interface." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=123268.

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Reinforced concrete structures are prone to corrosion in harsh environments. Fibre-Reinforced Polymer (FRP) laminates are more resistant than steel elements, such as bars and plate in aggressive environments; they can be used as a barrier to protect concrete structures; however, poor bond between FRP composite laminates and structural concrete can prevent utilizing the full structural and protective capacity of FRP-concrete composite system, therefore, it is important to develop good bond between concrete and the FRP to ensure the integrity and durability of the FRP-concrete system. There is a need to understand the bond characteristics at the FRP laminates-concrete interface, and the various parameters influencing the bond performance of the composite system. This research program consists of numerical modeling of the double lap pull-off tests conducted by Ali et.al (2012) and comparing the computed values with the experimental results for two different batches, along with an evaluation of the various parameters influencing bond between FRP laminates and concrete. The ABAQUS 6.10.1 program was used to model the double lap pull-off test. Shell elements were used to model FRP laminates, solid elements for concrete and steel and cohesive elements for modeling the epoxy joint. The constitutive models for the materials were selected based on their experimental behavior. A linear elastic model was used for modeling FRP laminates and steel, elastoplastic behavior was used for modeling epoxy and damaged plasticity model was used for modeling concrete.Numerical and experimental curves reflected similar responses. In the first batch the average ultimate load in the tests was 70.7 kN , while the ultimate load for the numerical analysis was 73.8 kN, showing a difference of 4.6% . Also, the average experimental value of strain at the center of the FRP laminate was 2657×〖10〗^(-6), while the ultimate strain in numerical simulation was 3023×〖10〗^(-6), showing an acceptable difference of 12.1 %. In the second batch, the average of experimental ultimate load was 54.5kN, while the ultimate load in numerical analysis was 58.6kN, with a difference of only 5.4%. The computed ultimate strain is 2320 ×〖10〗^(-6), while the average of ultimate strain in experimental study was 2173×〖10〗^(-6), showing a discrepancy of 6.3%. Also, the effect of different geometrical factors on the bond behavior of FRP and concrete was studied; it was concluded that, the most effective geometrical parameter influencing bond between FRP and concrete was the bonded width of the FRP laminate.
Les structures en béton armé sont sujettes à la corrosion dans des environnements difficiles. Dans ces conditions, les couches de polymère renforcé de fibres (PRF) sont plus résistants que les plaques d'acier, ils peuvent ainsi être utilisés comme une barrière pour protéger les structures en béton armé; Cependant, un faible (mauvais) collage entre les couches composites de PRF et le béton peut empêcher l'utilisation de la pleine capacité de ce composite. Par conséquent, il est important de développer une adhérence complète entre le béton et le PRF pour assurer l'intégrité et la durabilité de ce système.Il est nécessaire de comprendre les caractéristiques des liaisons à l'interface des couches de polymère renforcé de fibres - béton, et les différents paramètres influençant les performances de ces liaisons. Cet recherche comprend la modélisation numérique des essais de traction à recouvrement double effectués par Ali et.al (2012) et la comparaison des valeurs calculées avec les résultats expérimentaux pour deux groupes différents, avec une évaluation des paramètres influençant les liaisons entre les couches de polymère renforcé de fibres et le béton.Le programme d'éléments finis ABAQUS 6.10.1 a été utilisé pour l'analyse numérique d'essai en traction à recouvrement double. Des éléments coques ont été utilisés pour modéliser les couches de polymère renforcé de fibres, des éléments solides pour modéliser le béton et l'acier et des éléments de cohésion pour modéliser le joint en résine époxyde. Les modèles pour les matériaux ont été choisis en fonction de leur comportement expérimental. Un modèle élastique linéaire a été utilisé pour les couches de polymère renforcé de fibres et de l'acier, un modèle élasto-plastique a été utilisé pour la résine époxyde et le modèle de plasticité endommagée a été utilisé pour le béton.Les résultats entre les tests numériques et expérimentaux montrent une réponse similaire. Dans le premier groupe, la moyenne de la charge ultime des essais expérimentaux était égale à 70.7 kN tandis que celle de l'analyse numérique était égal à 73.8, ce qui montre une différence de 4.6%. De plus, la valeur moyenne expérimentale de la contrainte au centre des couches de PRF était égale à 2657×〖10〗^(-6), tandis que celle de la souche ultime dans la simulation numérique était de 3023×〖10〗^(-6), montrant une différence de 12.1%. Dans le deuxième groupe, la moyenne de la charge ultime expérimentale était égal à 54.5kN, alors que celle de l'analyse numérique était égale à 58.6kN, il y a donc une différence de seulement 5.4%. La contrainte ultime calculée était égale à 2320 ×〖10〗^(-6), alors que la moyenne de celle de l'étude expérimentale était égale à 2173×〖10〗^(-6), montrant une différence de 6.3%. Les effets de plusieurs facteurs géométriques sur les liaisons entre les couches de polymère renforcé de fibres et le béton ont été étudiés. Les résultats de cette enquête ont montré que le paramètre géométrique ayant le plus d'influence sur la liaison entre les couches de PRF et le béton était la largeur de ces liaisons.

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Wang, X., Q. Zheng, S. Dong, Ashraf F. Ashour, and B. Han. "Interfacial characteristics of nano-engineered concrete composites." Elsevier, 2020. http://hdl.handle.net/10454/17954.

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This study investigates the interfacial characteristics between aggregates and cement paste matrix in nanofillers modified concrete. A three-point bend test on the specimens composed of two pieces of aggregates bonded with a thin layer of cement pastes with/without nanofillers was carried out to characterize the interfacial bond strength of the composites. The scanning electron microscope observations and energy dispersive x-ray spectrometry analysis were also performed to characterize the interfacial microstructures and compositions of the composites. The experimental results indicated that the nanocomposites have higher interfacial bond strength and narrower interfacial transition zone thickness as well as more optimized intrinsic compositions and microstructures than that of composites without nanofillers. Specifically, the interfacial bond strength of nanocomposites can reach 7.67 MPa, which is 3.03 MPa/65.3% higher than that of composites without nanofillers. The interfacial transition zone thickness of nanocomposites ranges from 9 μm to 12 μm, while that of composites without nanofillers is about 18 μm. The ratio of CaO to SiO2 in the interface of composites without nanofillers is 0.69, and that of nanocomposites increases to 0.75–1.12. Meanwhile, the nanofiller content in nanocomposite interface is 1.65–1.98 times more than that in the bulk matrix. The interfacial microstructures of nanocomposites are more compact and the content and crystal size of calcium hydroxide were significantly reduced compared with that of composites without nanofillers.
The National Science Foundation of China (51978127 and 51908103), and the China Postdoctoral Science Foundation (2019M651116).

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Romero, Rodney Gray. "The histology of bone and its piezoelectric characteristics." Thesis, Kingston University, 1986. http://eprints.kingston.ac.uk/20508/.

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An investigation into the effects of micro electric currents on the material of bone is presented along with a review of the ideas and concepts associated with bone’s response to load and the alleged piezoelectric phenomena. A comparison is made between the structure of bone, its strength and stress generated potential. Evidence is forwarded to show that micro currents may influence the behaviour of bone material and it is demonstrated that these effects may be understood through reference to the limiting molar conductivities of the ions in the material and the solutions used.

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Ilvesaro, J. (Joanna). "Attachment, polarity and communication characteristics of bone cells." Doctoral thesis, University of Oulu, 2001. http://urn.fi/urn:isbn:9514259351.

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Abstract Bone resorbing osteoclasts require tight attachment of their plasma membrane to the bone surface in order to retain the specific microenvironment and thus to be able to dissolve the bone matrix underneath. Cadherins are transmembrane glycoproteins usually mediating homophilic calcium-dependent cell-cell adhesion. In the present work we have studied the effects of the cadherin CAR sequence HAV-containing hexapeptide AHAVSE on osteoclasts. The primary attachment of osteoclasts to bone surface is not affected by the peptide, suggesting that it is not mediated by cadherins. Treatment of osteoclast cultures with AHAVSE decreased the number of resorption pits and the total resorbed area. Furthermore, we show rapid inactivation of osteoclasts with AHAVSE, which is seen as a decrease in the percentage of osteoclasts with actin rings. Pan-cadherin antibodies localized cadherin-like molecule in the sealing zone area of osteoclasts. These results suggest that cadherin-like molecules may mediate the tight attachment of osteoclasts in the sealing zone area and that the decrease of resorption in AHAVSE-treated osteoclast cultures is due to prevention of sealing zone formation. We studied the polarity of mesenchymal osteoblasts using osteosarcoma cell line UMR-108 and endosteal osteoblasts in situ in bone tissue cultures. Immunofluorescence confocal microscopy revealed that the vesicular stomatitis virus glycoprotein (VSV G) was targeted to the culture medium-facing surface. In endosteal osteoblasts, VSV G protein was found in the surface facing the bone marrow and circulation. On the contrary, Influenza virus hemagglutinin (HA) was localized to the bone substrate-facing surface of the UMR-108 cells. Electron microscopy showed that VSV particles were budding from the culture medium-facing surface, whereas Influenza viruses budded from the bone substrate-facing plasma membrane. These findings suggest the bone attaching plasma membrane of osteoblasts is apical, and the circulation or bone marrow facing plasma membrane is basolateral in nature. Gap junctions often mediate communication between different cells and cell types. In the present work, we demonstrate that rat osteoclasts show connexin-43 staining localizing in the plasma membrane of the cells in cell-cell contacts and over the basolateral membrane of osteoclasts. The effects of heptanol and Gap 27, known gap- junctional inhibitors, were studied using the well-characterized pit formation assay. The inhibitors decreased the number and activity of osteoclasts, suggesting a defect in the fusion of mononuclear osteoclast precursors to multinucleated mature osteoclasts. Furthermore, the total resorbed area and the number of resorption pits also decreased in the cultures. These results suggest that gap-junctional connexin-43 plays a functional role in osteoclasts, and that the blocking of gap junctions decreases both the number and the activity of osteoclasts.

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Avsar, Casatay. "Breakage Characteristics Of Cement Components." Phd thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/2/587147/index.pdf.

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The production of multi-component cement from clinker and two additives such as trass and blast furnace slag has now spread throughout the world. These additives are generally interground with clinker to produce a composite cement of specified surface area. The grinding stage is of great importance as it accounts for a major portion of the total energy consumed in cement production and also as it affects the quality of composite cements by the particle size distribution of the individual additives produced during grinding. This thesis study was undertaken to characterize the breakage properties of clinker and the additives trass and slag with the intention of delineating their grinding properties in separate and intergrinding modes. Single particle breakage tests were conducted by means of a drop weight tester in order to define an inherent grindability for the clinker and trass samples in terms of the median product size ( ). In addition, a back-calculation procedure was applied to obtain the breakage rate parameters ( ) of perfect mixing ball mill model using industrial data from a cement plant. Kinetic and locked-cycle grinding tests were performed in a standard Bond mill to determine breakage rates and distribution functions for clinker, trass and slag. Bond work indices of these cement components and of their binary and ternary mixtures were determined and compared. Attempts were made to use back-calculated grinding rate parameters to simulate the Bond grindability test. The self-similarity law was proved to be true for clinker and trass that their shapes of the self-similarity curves are unique to the feed material and independent of the grinding energy expended and overall fineness attained. The self-similar behaviour of tested materials will enable process engineers to get useful information about inherent grindability and energy consumption in any stage of the comminution process. The parameters, and indicating the degree of size reduction were defined with different theoretical approaches as a function of energy consumption by using single particle breakage test data of clinker and trass. The breakage distribution functions were found to be non-normalizable. On the other hand, the breakage rate functions were found to be constant with respect to time but variable with respect to changing composition in the Bond ball mill. These variations are critical in computer simulation of any test aiming to minimize the experimental efforts of the standard procedure. As a result of the back calculation of breakage rate parameters for clinker and trass samples in the Bond mill, no common pattern was seen for the variation of the rate parameters. Therefore, computer simulation of the Bond grindability test did not result in an accurate estimation of the Bond work index.

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Shalhoob, Hebah Shafeq. "A comparative analysis of risk-return characteristics between Sukuk (Islamic bonds) and conventional bonds." Thesis, Robert Gordon University, 2016. http://hdl.handle.net/10059/1574.

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Sukuk are an important mode of financing in the Islamic financial system. As usury (interest) is prohibited in Islam, conventional bonds are not suitable for investors in Islamic countries. Since their launch in the 1980s, Sukuk have gained recognition and popularity as a substitute for conventional bonds. However, their unique features mean that Sukuk are not always clearly understood. The aim of this study is to analyse the differences and similarities between Sukuk and conventional bonds in terms of their risk and return characteristics.

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Ohman, Anna Maria Caroline <1980&gt. "Human bone: the tissue characteristics determining its mechanical behaviour." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/3784/.

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The present thesis illustrates the research carried out during the PhD studies in Bioengineering. The research was aimed to characterise the human bone tissue, with particular regard to the differences between cortical and trabecular bone. The bone tissue characteristics that affect its mechanical properties were verified or identified, using an experimental approach, to corroborate or refute hypotheses based on the state of the art in bone tissue biomechanics. The studies presented in the present PhD thesis were designed to investigate aspects of bone tissue biomechanics, which were in need of a more in-depth examination since the data found in the literature was contradictory or scarce. In particular, the work was focalised on the characterisation of the basic structure of the bone tissue (groups of lamellae), its composition, its spatial organisation (trabecular bone microarchitecture) and their influence on the mechanical properties. In conclusion, the present thesis integrates eight different studies on the characterisation of bone tissue. A more in-depth examination of some of the aspects of bone tissue biomechanics where the data found in the literature was contradictory or scarce was performed. Bone tissue was investigated at several scales, from its composition up to its spatial organization, to determine which parameters influence the mechanical behaviour of the tissue. It was found that although the composition and real density of bone tissue are similar, the differences in structure at different levels cause differences between the two types of bone tissue (cortical and trabecular) in mechanical properties. However, the apparent density can still be considered a good predictor of the mechanical properties of both cortical and trabecular bone. Finally, it was found that the bone tissue characteristics might change when a pathology is present, as demonstrated for OA.

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Lim, Ee Yeong. "Bond strength and characteristics of Carbon Fibre Reinforced Plastic, CFRP, bars in concrete beams." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0034/MQ62242.pdf.

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Elagroudy, Hossam Aly. "BOND CHARACTERISTICS OF MICRO-COMPOSITE MULTI-STRUCTURAL FORMABLE STEEL USED IN REINFORCED CONCRETE STRUCTURES." NCSU, 2003. http://www.lib.ncsu.edu/theses/available/etd-07252003-213630/.

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The bond performance of a unique type of reinforcing steel rebars, claimed to have high corrosion resistance as well as high tensile strength, with concrete was studied. The objective was to investigate the bond behavior of straight rebars made out of this steel, named MMFX, embedded in concrete flexural members and to examine the applicability of the current expressions for bond force to predict the bond capacity of the MMFX bars embedded in concrete. Two phases of experimental investigation was conducted. In the first phase, four beam end specimens were tested and in the second phase eight splice beams were studied. The bond behavior of the MMFX steel bars was found to be similar to that of carbon steel. The bond strength of the MMFX is significantly reduced as the tensile stresses developed in the bar went beyond the proportional limit. Both the ACI code 318-02 equation for bond force and the current equation proposed by the ACI committee 408 for bond force gave conservative prediction for bond force for low stress levels. However, at high stress levels, the prediction of the two equations went to the unconservative side. The non linear behavior of the MMFX stress-strain curve was the reason behind the unconservative prediction. The above two equations were modified to ensure conservative prediction at high stress levels. A second degree best fitting curve was found to be the best to describe the relationship between the splice length and the bond force capacity for both # 6 and # 8 MMFX bars.

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Holste, Joseph Robert. "Experimental determination of prestressing wire bond and splitting propensity characteristics through tensioned pullout tests." Diss., Kansas State University, 2014. http://hdl.handle.net/2097/17383.

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Doctor of Philosophy
Department of Civil Engineering
Robert J. Peterman
This dissertation describes a testing program to evaluate the bond and splitting propensity characteristics of 5.32-mm-diameter prestressing wires. Prestressing wire reinforcement is used primarily in the production of prestressed concrete railroad ties. Twelve different 5.32-mm-diameter wires were tested in this study in order to measure bonding characteristics of the reinforcement. Establishment of the bond-slip characteristics of these reinforcement at both transfer of prestress (transfer bond) and under flexural loading (flexural bond) is necessary to enable the accurate modeling of these ties using finite elements. Transfer bond and flexure bond of various indent patterns were tested using tensioned pullouts. Specimens of various sizes with single or multiple wires were tested to determine the effects of cover and wire number on bond. Indents were machined on smooth prestressing wires to accurately compare indent geometries. Lateral expansion was tested to determine which wires have higher propensity to cause cracking or splitting. Crossties were instrumented to compare resulting lateral expansion with results found in the laboratory. The results from the testing program showed that the tensioned pullout test was able to be used to predict the transfer length of prisms made with the same reinforcement. The results also showed that the indent geometries were able to be used to predict the splitting of specimens based on the amount of slip the wire had experienced. The testing also showed the importance of concrete cover with the relation to splitting potential.

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20

Maléř, Pavel. "Návrh pracovního bodu odstředivého čerpadla." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228299.

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The diploma thesis has a target to create a computer program that will serve as help for an evaluation of the system of pumps (The Operating Point of the Centrifugal Pump). The computer program is intended above all designers, but it will find its using in the sphere of education. The main computer program has two partial programs: System characteristic and Performance characteristic. The main point of this diploma thesis is create partial computer program: system characteristic. Other target is creating the main program and finding The Operating Point of the Centrifugal Pump. Other parameters are power efficiency, flow, specific energy for pump or pumps. These parameters are important for correct and economical proposal.

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21

Peled, Alva. "Cement Penetrability Characteristics in Textile Cement Systems." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1244044138771-75495.

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Cement penetrability is a key factor in multifilament cement composites. However, the modes of action and the concepts vary because of brittle and ductile fibers. In the case of brittle fibers such as glass, high penetrability of cement products in between the bundle filaments can lead to brittle composite behavior, and therefore addition in ductility is required. In order to have efficient bundle action and high bonding, fillers can be introduced in between the glass filaments, keeping the telescopic mode of failure but at the same time improving the bond and stress transfer within the filaments of the bundle, even at late ages, resulting in a ductile and high strength composite. On the other hand, ductile fibers such as polypropylene (PP), which also developing low bonding with the cement matrix, result in ductile cement composite but with relatively low strength. Therefore, in this case good penetrability of the cement in between the filaments of the bundle is essential in order to maximize the reinforcing efficiency of the bundle by improving bond. The penetrability of the matrix into a fabric structure and especially in between the bundle filaments made up the fabric is a result of fiber- matrix compatibility, which depends on: level of opening and spaces between the filaments, bundle surface properties including wetting and chemical affinity to the cement matrix, matrix viscosity, processing of the composite, and the nature of the fabric junctions and the resulting tightening effects of the bundle, i.e., influenced by the fabric structure itself.

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22

Ong, Fook Rhu. "Analysis of bone drilling characteristics for the enhancement of safety and the evaluation of bone strength." Thesis, Loughborough University, 1998. https://dspace.lboro.ac.uk/2134/13900.

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Bone drilling is a major part of modern orthopaedic surgery associated with the principles of internal fixation of fractured bones. At present, information related to drilling forces, rate of drill bit penetration and drill bit rotational speed is not available to orthopaedic surgeons, clinicians and researchers as bone drilling is performed manually. This research demonstrates that orthopaedic surgery involving the drilling of bone can greatly benefit from the technology of automation/ mechatronics, which allows the collection and storage of the drilling data for analysis as well as for the improvement of the drilling procedure. The research also represents a significant contribution to the development of a drilling system for the enhancement of safety and/or as a diagnostic tool for the evaluation of bone strength. A novel automated experimental rig, which enables drilling tests to be carried out in a controlled environment, has been developed. The investigation for the enhancement of safety involves the detection of drill bit break-through on a femoral shaft in the presence of system compliance and inherent fluctuation of drilling forces. Since these two factors affect the detection of drill bit break-through, a robust and reliable method based on a modified Kalman filter has been developed. When applied to the force difference between successive samples and the rotational speed, the modified Kalman filter has been found to be very effective in establishing trends and ironing out major fluctuations caused by the system compliance and inherent drilling force fluctuation. The evaluation of bone strength related to the cancellous bone at the proximal femur has resulted in the establishment of a positive relationship between the average drilling force and bone mineral density (BMD), obtained from bone densitometry, which is used to estimate bone strength in clinical practice. The correlation has been found to depend on the direction of drilling. This is indicated by a linear relationship obtained in the anterior-posterior direction (perpendicular to the cervical axis), which is not interchangeable with the relationship in the direction of the cervical axis. Findings of this research have indicated that analysis of bone drilling forces has the potential to provide additional information about the strength of bone.

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23

Bozkurt, Ozlem. "Study Of Bone Characteristics And Muscle Quality In Metabolic Disorders." Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614561/index.pdf.

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Although the effects of diabetes on bone mineral content has been studied, little is known about the structural alterations in collagen, maturation of apatite crystals and carbonate content in diabetic bone. The first part of this study aimed to investigate the mineral and organic properties of cortical, trabecular and growth plate regions of rat femur tissues in type I diabetes using FTIR microspectroscopy and Vickers microhardness test. A decrease in mineral content (degree of mineralization), decrease in microhardness, increase in carbonate content, increase in size and maturation of hydroxyapetite crystals, which are the implications of increased osteoporosis, were observed in diabetic bone. In addition, a decreased carbonate substitution into bone apatite and an increase in labile type carbonate was observed in diabetic bone. There was a decrease in the level of crosslinking of collagen in cortical and trabecular regions of diabetic femurs, implying a decrease in bone collagen quality that may contribute to bone fragility. Recent evidence implies that intramyocellular lipid accumulation is directly correlated with insulin resistance, a key parameter in the generation of obesity. The second part of this study is mainly focused on the determination of the structural and compositional characterization of macromolecules of longissimus dorsi and quadriceps muscles of Berlin fat mouse inbred (BFMI) lines using ATR-FTIR spectroscopy and FTIR microspectroscopic imaging, together with the quantification of fiber specific distribution of lipids in these muscles by the use of confocal microscopy. The study groups included 10 weeks old standard breeding diet fed (juvenile) and 20 weeks old high fat diet fed control and BFMI lines. The results revealed the loss of unsaturation in lipids, increased triglyceride content, increased amount of lipids having shorter chain length, increased lipid peroxidation and fiber specific accumulation of lipids in type IIa and intermediate fibers in skeletal muscles of both 10 weeks old and 20 weeks old BFMI lines, emphasizing their obese phenotype. However, the alterations were more prominent in skeletal muscles of 20 weeks old high fat diet fed BFMI lines, displaying a more severe obesity phenotype. The results of the characterization revealed that BFMI860 and BFMI861 lines are convenient models for the study of spontaneous obesity and studies to enlighten the genetic basis of obesity.

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24

Iniotakis, C., N. Hayashi, Y. Sawa, T. Yokoyama, U. May, Y. Tanaka, and M. Sigrist. "Andreev bound states and tunneling characteristics of a noncentrosymmetric superconductor." American Physical Society, 2007. http://hdl.handle.net/2237/11288.

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25

Toljamo, P. (Päivi). "Dual-energy digital radiography in the assessment of bone characteristics." Doctoral thesis, Oulun yliopisto, 2015. http://urn.fi/urn:isbn:9789526209319.

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Abstract Today, the diagnosis of osteoporosis and assessment of fracture risk is based on estimation of bone mineral density (BMD) determined by dual-energy X-ray absorptiometry (DXA). A lack has been shown in the prediction of individual fracture risk using DXA-based BMD (BMDDXA). Digital radiography (DR) has eased the application of dual-energy techniques for separating bone and soft tissue, but the direct application of dual-energy digital radiography (DEDR) to determine BMD has not been investigated. Additionally, with BMD and bone mass, bone geometry affects strongly the mechanical strength of bone. Geometrical parameters can also be determined from the DR images. This study aimed to investigate the ability of DEDR to determine BMD and whether the combination of DEDR-based BMD and geometry improves the prediction of maximal load. Fracture and osteoporosis diagnoses could thus be done with one examination, i.e. with DEDR, whereas in the current routine both DR imaging and DXA examination are needed for diagnoses. Reindeer femora were imaged by DR with two different energies (79 and 100 kVp). The different geometrical parameters were also determined from the 79 kVp images. The BMD measured by DEDR (BMDDEDR) were calculated using the calculation principle of DXA. The ability of BMDDEDR to predict BMDDXA was investigated. The femora were mechanically tested in an axial loading configuration with the shaft in a vertical position to determine mechanical parameters. The best combination of BMDDEDR and geometrical parameters to predict bone maximal load was explored. BMDDXA was used for comparison. Significant moderate to high linear correlations were observed in all regions of the upper femur (femoral neck, Ward’s triangle, trochanter and inter-trochanter) between BMDDEDR and BMDDXA. BMDDEDR of the femoral neck and BMDDXA of the femoral neck predicted maximal load similarly. The best combination of parameters to predict maximal load was BMDDEDR at Ward’s triangle, femoral shaft diameter (FSD) and femoral shaft axis length (FNAL) (r = 0.79, p < 0.05). The study shows that DEDR is a suitable method to determine BMD in vitro and the combination of BMD and geometry improves the prediction of bone maximal load when compared to BMDDEDR of femoral neck or trochanter only. The thesis also includes unpublished data from a preliminary human study
Tiivistelmä Osteoporoosin diagnosointi ja murtumariskin määrittäminen perustuvat kaksienergisellä röntgenabsorptiometrialla (DXA) mitattavaan luun mineraalitiheyden (BMD) arviointiin. DXA:lla määritetyn luun mineraalitiheyden (BMDDXA) on kuitenkin osoitettu olevan puutteellinen murtumariskin yksilöllisessä ennustamisessa. Digitaalinen röntgenkuvaus (DR) on helpottanut sellaisten kaksienergisten tekniikoiden toteuttamista, joissa luu ja pehmytkudos on eroteltu toisistaan. Kaksienergisen digitaalisen röntgenkuvausmenetelmän (DEDR) soveltamista BMD:n määrittämiseen ei ole tutkittu. BMD:n ja luun massan lisäksi on luun geometrialla vahva vaikutus luun mekaaniseen lujuuteen. Geometriset parametrit voidaan määrittää niin ikään digitaalisista röntgenkuvista. Tässä työssä tutkittiin, pystytäänkö DEDR:llä määrittämään BMD sekä parantaako DEDR:llä mitattujen BMD:n ja geometrian yhdistelmä luun maksimikuormituksen ennustetta. Näin ollen murtuma- ja osteoporoosidiagnoosit voitaisiin tehdä yhdellä tutkimuksella (DEDR), kun nykyisin diagnoosit vaativat sekä digitaalisen röntgenkuvauksen että DXA-tutkimuksen. Poron reisiluut kuvattiin digitaalisen röntgenlaitteen kahdella eri kuvausjännitteellä (79 ja 100 kVp). 79 kVp -kuvista määritettiin myös erilaiset geometriaparametrit. BMD laskettiin DEDR-kuvista (BMDDEDR) DXA:n laskentaperiaatetta käyttäen. BMDDEDR:n kyky ennustaa BMDDXA:a tutkittiin. Maksimikuormituksen selvittämiseksi reisiluut testattiin mekaanisesti aksiaalisuunnassa varren ollessa pystysuorassa asennossa. BMDDEDR- ja geometriaparametreista määritettiin paras yhdistelmä maksimikuorman ennustamiseen. BMDDXA-arvoja käytettiin analysoinnissa vertailun vuoksi. BMDDEDR- ja BMDDXA-arvojen välillä havaittiin merkitsevä keskinkertainen tai korkea korrelaatio kaikissa mielenkiintoalueissa (reisiluun kaula, Wardin kolmio, sarvennoisen alue ja reisiluun varren alue). Wardin kolmiosta mitatun BMD:n (WABMDDEDR), reisiluun varren halkaisijan (FSD) ja reisiluun kaulan kautta kulkevan akselin (FNAL) yhdistelmä ennusti parhaiten luun haurautta (r = 0.79, p < 0.05). Tutkimus osoittaa, että DEDR on sopiva menetelmä BMD:n määrittämiseen tutkimusolosuhteissa ja että BMD:n ja geometrian yhdistelmä parantaa maksimikuormituksen ennustetta pelkästään reisiluun kaulasta tai sarvennoisesta mitattuun BMDDEDR:iin verrattuna. Väitöskirja sisältää myös julkaisemattomia tuloksia alustavista ihmistutkimuksista

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26

Holste, Joseph Robert. "Evaluating time-dependent and bond characteristics of a lightweight concrete mix for Kansas prestressed concrete bridges." Thesis, Kansas State University, 2010. http://hdl.handle.net/2097/6998.

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Master of Science
Department of Civil Engineering
Robert J. Peterman
This thesis details findings from testing done to determine bond and time-dependent characteristics of two lightweight concrete mixes. The lightweight mixes were tested to possibly provide a more cost-effective solution to replacing some of Kansas’ older bridges. Testing included use of a conventional lightweight mix and a self-consolidating lightweight mix. Sixteen Inverted T-beams were cast at a prestress plant to determine prestress losses that had occurred in the two lightweight mixes. These losses were compared to ACI, PCI, and AASHTO code equations. Creep and shrinkage prisms were also cast and measured to accurately determine creep and shrinkage variables for the two lightweight mixes. Twelve flexural beams were also cast at the prestress plant and tested at Kansas State University’s Civil Engineering Structures Laboratory to experimentally test development lengths of the lightweight mixes and to compare results with ACI code equations. This study found compressive strengths of the lightweight concrete mixes varied greatly from laboratory testing. Low concrete strengths caused the prestress losses to be greater than the predicted code values. Flexure beam testing showed several of the beams were subject to strand slip, causing a sudden violent failure.

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27

Piper, James Wilson. "Force dependence of cell bound E-selectin/carbohydrate ligand binding characteristics." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/18388.

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28

Robinson, Joseph K. "The role of bound water content in defining sludge dewatering characteristics." Thesis, Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/50083.

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Several available methods of measuring sludge bound water content in the laboratory were examined. The effect of polymer conditioning on the bound water content of biological sludge samples was measured using the dilatometric method. The effects of mechanical dewatering on the bound water content of biological sludge samples and on chemical sludge samples was measured using the same method. The controlled drying method was used to measure the effect of polymer conditioning and mechanical dewatering on the chemically bound water fraction. The relationship between bound water content and cake solids concentration was examined, as well as the relationship between cake solids concentration and sludge bulk density. The role of apparent sludge floc density was examined. The dilatometric method was found to be the most accurate and most convenient method for measuring the chemically bound water fraction. Polymer conditioning was found to release significant volumes of bound water. Further bound water release was produced by mechanical dewatering. The amount of bound water released increased with the degree of mechanical dewatering pressure applied. The chemically bound water fraction was not affected by polymer conditioning or mechanical dewatering. A reduction in bound water brought about a corresponding increase in cake solids concentration. Sludge bulk density increased with cake solids concentration. Apparent sludge floc density of the unconditioned, underwatered sludge sample was predictive of ultimate dewatering performance in many cases.
Master of Science
incomplete_metadata

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Le, Dat Quang. "A Comparative Analysis of Success by Project Level Characteristics in the Upward Bound Program." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/26958.

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Data gathered by Mathematica Policy Research, Inc., contractor for the Department of Education were used to analyze successful project level characteristics of the Upward Bound program. Mathematica Policy Research, Inc. provided two data files for this study: a student data file and a grantees data file. The first data file includes information from a nationally representative sample of students who applied to the Upward Bound program between 1992 and 1994 and were assigned to either the Upward Bound group or a control group. The second data file included information from a random sample of Upward Bound project grantees. Both the student and grantees data files were used to create a design to determine Upward Bound project level characteristics that highly correlated to student success. The project level characteristics that were examined included project setting (location, size and host institution), academic characteristics (student-staff ratio, course offerings during the summer and academic year, and the number of years a project has been in operation) and student characteristics (gender, race/ethnicity and employment). The student success measures used in this study included grade point average, total high school credits earned, Advanced Placement credits earned, high school dropout status and graduation status. Findings from this study suggest that Upward Bound projects with lower student to staff ratios and fewer academic year course offerings have students earning more high school credits and more student graduating from high school. In addition to academic characteristics, ethnicity seem to be related to the success of projects. When compared across project settings, projects from two-year rural colleges and four-year public suburban colleges have the most successful students.
Ph. D.

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30

Liu, Jing. "Effects of Bond Coat Surface Preparation on Thermal Cycling Lifetime and Failure Characteristics of Thermal Barrier Coatings." Master's thesis, University of Central Florida, 2004. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4410.

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Thermal barrier coatings (TBCs) have been widely used in gas turbine engines to protect the underlying metal from high operating temperature so as to improve the durability of the components and enhance the engine efficiency. However, since the TBCs always operate in a demanding high-temperature environment of aircraft and industrial gas-turbine engines, a better understanding of this complex system is required to improve the durability and reliability. The objective of this study is to investigate the effects of surface modification for the NiCoCrAlY bond coats on the thermal cycling lifetime and failure characteristics of TBCs. Parameters of modification for the bond coats included as-sprayed, barrel-finished, hand-polished and pre-oxidation heat treatment at 1100[degrees]C in P=10O2-8 atm up to 4 hours, carried out prior to the electron beam physical vapor deposition (EB-PVD) of ZrO2-7wt% Y2O3 (7YSZ) ceramic topcoat. The resulting characteristics of the bond coat and the thermally grown oxide (TGO) scale were initially documented by surface roughness, phase constituents of the TGO scale, and residual stress of the TGO scale. The thermal cycling test consisted of 10-minute heat-up to 1121°C, 40-minute hold at 1121°C, and 10-minute forced air-quench. As-coated and thermally-cycled TBCs were characterized by optical profilometry (OPM), photo-stimulated luminescence spectroscopy (PSLS), optical microscopy, scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS), and scanning/transmission electron microscopy (TEM/STEM) equipped with high angle annular dark field (HAADF) and X-ray energy dispersive spectroscopy (XEDS). TBC specimens for TEM/STEM analysis were prepared by focused ion beam (FIB) in-situ lift-out (INLO) technique. Superior thermal cycling lifetime was observed for TBCs with as-sprayed bond coats regardless of pre-oxidation heat treatment, and TBCs with hand-polished bond coats only after pre-oxidation heat treatment. With pre-oxidation heat treatment, relative photostimulated luminescence intensity of the equilibrium α-Al2O3 increased. Thus, the improvement in TBC lifetime can be correlated with an increase in the amount of α-Al2O3 in the TGO scale, given a specific surface modification/roughness. The lifetime improvement due to pre-oxidation was particularly significant to TBCs with smooth hand-polished bond coats and negligible for TBCs with rough as-sprayed bond coats. Spallation-fracture paths depended on the lifetime of TBCs. Premature spallation of TBCs occurred at the interface between the YSZ and TGO. Longer durability can be achieved by restricting the fracture paths to the TGO/bond coat interface. Small particulate phase observed through the TGO scale was identified as Y2O3 (cubic) by diffraction analysis on TEM. While small addition of Y in the NiCoCrAlY bond coat helps the adhesion of the TGO scale, excessive alloying can lead to deleterious effects.
M.S.
Department of Mechanical, Materials and Aerospace Engineering
Engineering and Computer Science
Mechanical, Materials and Aerospace Engineering

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Gabriel, Paul G. "Characteristics and outcomes of advanced refunding of school construction bonds in Indiana." Virtual Press, 1998. http://liblink.bsu.edu/uhtbin/catkey/1117122.

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This study examined advanced refundings of Indiana school construction bonds from 1993 to 1996. Purposes were to: (a) add to the professional knowledge base about advanced refundings; (b) evaluate the financial consequences on taxpayers; (c) determine benefits as measured by interest rates, terms, and payment amounts; (d) determine whether selected financial conditions and demographic variables impacted refunding outcomes.The population was all instances of advanced refundings by Indiana public school districts in the period studied. Data were collected from the bond transcripts prepared by legal counsels and placed in tabulation forms developed for the project.Primary findings included:(a) Three quarters of the refunding occurred in the first 10 years of the paymentstream; 27% occurred in the first four years.(b) As the size of the issue increased, the cost (as a percentage of the issue)decreased.(c) Mean decrease in interest rate for the refizndings was .023915 or 239 basis points.(d) Net fiscal impact was generally positive, with a mean savings of $224,218. (e) A negative correlation existed between district wealth and annual paymentamount (i.e., districts with high assessed valuations had smaller changes inannual payments).(f) A positive correlation existed between interest rate change and refunding amount (i.e., large issues were more sensitive to slight changes in interest rates).Selected conclusions included:(a) The benefits of refunding diminished with time (i.e., greatest benefits are likely in the first quarter of the payment stream).(b) Some refundings occurred when the decline in basis points was below a standard level used for municipal bonds; this suggests that school officials may engage in refundings for reasons that extend beyond savings (e.g., political benefits).(c) An economy of scale between refunding size and costs supports existing research.(d) Costs for local school district counsel varied considerably, suggesting that no compensation standard was used.(e) Wealthier districts were less interested in lowering annual payments; their pursuit of refunding may have been motivated by flexibility (i.e., shortening the debt life, accessing fiscal resources).(f) Districts with large bond issues benefited from refunding even when the declines in interest rates were slight.Eight recommendations were formalized.
Department of Educational Leadership

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32

De, Santis Silvia, Giulia Di Pietro, Mauro Rebuzzi, and Silvia Capuani. "High field MR microimaging investigation gives more insights on spongy bone characteristics." Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-186404.

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Spongy-bone is a porous system characterized by a solid trabecular network immersed in bonemarrow and characterized by a different relative percentage of water and fats. In our previous paper, we demonstrated using calf bone samples, that water is more prevalent in the boundary zone while fats are rearranged primarily in the central zone of each pore. Moreover we showed that water internal gradient (Gi) magnitude from the samples was directly proportional to their trabecular bone density. Using a 9.4T MR micro-imaging system, here we evaluated T2, T2*, apparent diffusion coefficient (ADC) and Gi parameters from in vitro calf samples in spatially resolved modality, for both water and fat components. Moreover, relative percentages of water and fats were quantified from spectra. T2, T2* and ADC values are higher in fat than in water component. Moreover, the differential effects of fat and water diffusion result in different T2 and Gi behaviours. Our results suggest that differently from fat parameters, water T2*, ADC and Gi, may be reliable markers to assess not only trabecular bone density but, more generally, the status of spongy bone.

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De, Santis Silvia, Giulia Di Pietro, Mauro Rebuzzi, and Silvia Capuani. "High field MR microimaging investigation gives more insights on spongy bone characteristics." Diffusion fundamentals 14 (2010) 6, S. 1-4, 2010. https://ul.qucosa.de/id/qucosa%3A13855.

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Spongy-bone is a porous system characterized by a solid trabecular network immersed in bonemarrow and characterized by a different relative percentage of water and fats. In our previous paper, we demonstrated using calf bone samples, that water is more prevalent in the boundary zone while fats are rearranged primarily in the central zone of each pore. Moreover we showed that water internal gradient (Gi) magnitude from the samples was directly proportional to their trabecular bone density. Using a 9.4T MR micro-imaging system, here we evaluated T2, T2*, apparent diffusion coefficient (ADC) and Gi parameters from in vitro calf samples in spatially resolved modality, for both water and fat components. Moreover, relative percentages of water and fats were quantified from spectra. T2, T2* and ADC values are higher in fat than in water component. Moreover, the differential effects of fat and water diffusion result in different T2 and Gi behaviours. Our results suggest that differently from fat parameters, water T2*, ADC and Gi, may be reliable markers to assess not only trabecular bone density but, more generally, the status of spongy bone.

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34

Adebayo, Olabisi. "The influence of surface characteristics on adhesion to enamel and dentine." Connect to thesis, 2009. http://repository.unimelb.edu.au/10187/6618.

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This body of research investigated the bonding efficiency of self-etching primer adhesives to enamel and dentine with various surface characteristics. A series of preliminary experiments was carried out to determine the effect of operator experience, dentine tubule orientation, bond strength test method and resin composite material used on bond strengths. The results of the preliminary tests concluded that it is essential to develop skills in material handling and the test methods used; 2-step self-etching primer adhesives exhibit higher but more variable microshear bond strengths (µSBS) than ‘all-in-one’ adhesives on dentine at different depths and tubule orientations; fracture toughness and bond strength test results suggest that the fracture toughness of a resin composite may not be of significant influence on microtensile and µSBS tests outcomes for nano-filled hybrid materials.
An investigation of the bonding ability of self-etching primer adhesives under various tooth preparation conditions was carried out. Enamel and dentine specimens were prepared from human teeth and finished with various rotary cutting instruments and the erbium, chromium:yttrium, scandium, gallium, garnet laser. Specimens were bonded with two 2-step self-etching primer adhesives and two ‘all-in-one’ adhesives with a resin composite. The results showed that one of the 2-step adhesives exhibited higher but more variable µSBS than the ‘all-in-one’ adhesives and a silorane-based self-etching primer adhesive system to enamel and dentine.
The relationship between enamel microhardness and µSBS was evaluated. Enamel specimens were prepared and finished with one half of the surface tested for hardness using the Vickers test. The other half of the enamel surface was bonded using either a 2-step self-etching primer adhesive or an ‘all-in-one’ adhesive and a hybrid resin composite. Mean Vickers hardness numbers and µSBS for each enamel surface were calculated. Analysis using Pearson’s parametric test for regression analysis evaluated the correlation between Vickers hardness and µSBS. The results revealed a weak negative insignificant correlation between VHN and µSBS for the 2-step adhesive and no correlation for the ‘all-in-one’ adhesive.
The effect of conditioning and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on bonding to bleached and unbleached enamel was investigated. Four groups of enamel specimens: untreated control; bleaching with 16% carbamide peroxide gel for 90 min daily x 14 days; treated with CPP-ACP paste (Tooth Mousse, GC Corp., Japan) for 60 min daily x 7 days and bleached and CPP-ACP-treated were used. The specimens were divided into a further two groups and bonded with a total-etch adhesive or a 2-step self-etching primer adhesive. Specimens bonded with the self-etching primer adhesive were sub-divided into four conditioning subgroups before bonding: no conditioning; 30 – 40% phosphoric; 15% EDTA; 20% polyacrylic acid. Specimens were tested in shear mode until failure and analysed by 2-way ANOVA, one-way ANOVA and Tukey’s post-hoc test. The µSBS of the total-etch adhesive was not affected by enamel treatment. Bleaching reduced the µSBS of the self-etching primer adhesive but preconditioning with phosphoric acid and polyacrylic acid improved bond strengths after CPP-ACP application. Bond failure analysis revealed a predominance of adhesive failures after bleaching, but prior conditioning reduced the proportion of adhesive failures. Scanning electron microscopy (SEM) revealed that the interfacial morphology produced by the 2-step self-etching primer adhesive was independent of enamel treatment except after bleaching. Phosphoric acid etching was not inhibited by CPP-ACP treatment. Resin tag formation was observed with prior phosphoric acid and polyacrylic acid conditioning.
The effect of conditioning and CPP-ACP application on dentine bonding was also investigated. Dentine specimens with and without the smear layer were prepared and divided into a further two groups, CPP-ACP paste applied to one group for 60 min daily x 7 days and the other group was untreated. The two groups were divided into three subgroups for conditioning: no conditioning; 30 - 40% phosphoric acid; 20% polyacrylic acid. The dentine was bonded using a 2-step self-etching primer adhesive and an ‘all-in-one’ adhesive, and tested as previously described. Statistical analysis was carried out using one-way ANOVA and Tukey’s post-hoc test at α = 0.05. The results showed that the µSBS of both adhesives were not significantly affected on smear-covered dentine but was affected on smearless dentine. Conditioning did not improve bond strengths. Bond failure analysis showed more adhesive failures for the ‘all-in-one’ adhesive, particularly on smearless dentine and with prior polyacrylic acid conditioning. SEM revealed a similar morphology of the bonded interface for the 2-step self-etching primer adhesive regardless of conditioning; and areas of bond failures for the ‘all-in-one’ adhesive.
The 2-step self-etching primer adhesives exhibited higher bond strength and more regular bond integrity than the ‘all-in-one’ adhesives, as shown on the SEM observations. However, the ‘all-in-one’ adhesives exhibited less variability in bond strengths to tooth surface characteristics.

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Yazdifar, Mohammadreza. "A novel, internally structured stainless steel implant with titanium characteristics." Thesis, Brunel University, 2018. http://bura.brunel.ac.uk/handle/2438/16866.

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There are many aspects that have direct effects on total hip replacement performance (THR), such as material properties, applied loads, surgical approach, femur size and quality, prosthesis design, bone-implant interface etc. Bone mechanics and traditional implant materials cause a frequent problem for patients of total hip arthroplasty (THA): the bone becomes shielded from the loading. Bone structure follows what is called "Wolff's Law", meaning it has an adaptive structure, which alters its geometry when experiencing forces over its life (Goldstein, 1987); (Pearson & Lieberman, 2004). The improved femoral stems act weakly in transferring stress onto the remnant bone and bone tissue atrophies at the interface, which will result in loosening of the implant, pain and thus, revision surgery will need to take place to correct the issue ( Feldt, 2011). For the current study, an innovative hollow spherical structure is developed for femoral hip stems. The aim is to extract volume in the spherical shape from the stainless steel hip implant stems, in order to focus solely on correlating with titanium behaviour. Internal geometry for the femoral stem is optimised in order to transfer more stress onto the bone. Moreover, the approach involves extracting volume in the spherical shape from internal structure to reduce stress shieling. New novel implant is proposed that demonstrated reduction in stress shielding. A new structure has been developed in this study for biomedical applications, such as implants, with the aid of the rule of mixtures and finite element analysis was applied to various models with different complex internal structures. Firstly, the rule of mixtures was used as finite element could not handle the simulation due to the large number of elements created, and also helped developing the designs analysed in this study. Secondly, computational analysis was applied to simplified finite elements containing hollow spheres in their outer shell. Moreover, a compression test was applied to a solid sample and the experimental case. This approach was adopted to investigate the effects of a hollow structure near the side surface and the bone-implant interface. The same method was applied to samples containing uniformly distributed hollow spheres. In the both scenarios, the specimens were designed differently based on the sphere size, their distance from wall and that from each other. Finally, finite element was applied to actual implant samples containing hollow spheres. The sphered models have a smaller Young's modulus and strength than the solid stainless steel sample. The spheres in hollowed structures reduce the stress shielding and they transfer more stress onto the bone when compared to the solid stainless steel models. This approach also involves restructuring a hard material, such as stainless steel, to enhance osseointegration. The reduction of the Young's modulus and stress directly depends on the volume of the hollow spheres in the models; however, there is certain volume that can be extracted from solid.

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Tengstrand, Birgitta. "Rheumatoid arthritis in male patients : sex hormones, bone mineral density and clinical characteristics /." Stockholm, 2003. http://diss.kib.ki.se/2003/91-7349-531-X/.

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Hyder, A. H. M. Golam. "Sorption Characteristics of Hexavalent Chromium [Cr(VI)] onto Bone Char and Bio-char." Thesis, KTH, Mark- och vattenteknik (flyttat 20130630), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-171833.

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The sorption characteristics of hexavalent chromium [Cr(VI)] onto bone char and bio-char were evaluated as a function of pH, initial Cr(VI) concentration, and dosages of bone char and bio-char. Batch tests were conducted by using synthetic wastewater in this study. The effects of various initial Cr(VI) concentrations between 5 mg/L and 1000 mg/L were evaluated using bone char as a sorbent. A Cr(VI) removal efficiency of 100 % was achieved at pH 1 with 2 g of bone char in 50 mL of solution at 3 hours of reaction time using initial Cr(VI) concentration of 10 mg/L. About 100 % of Cr(VI) was removed at pH 2 with initial Cr(VI) concentrations of 10 mg/L using 4 g of bio-char in 200 mL of solution at 5 hours of reaction time. The initial Cr(VI) concentrations were varied between 10 mg/L and 500 mg/L when bio-char was used as the sorbent. The maximum sorption capacities of bone char and bio-char were determined to 6.46 mg Cr(VI)/g, and 1.717 mg Cr(VI)/g, respectively. Equilibrium, kinetics, and isotherms of the sorption process were also investigated. The sorption kinetics of Cr(VI) onto bone char and bio-char followed the second order kinetic model suggesting that the sorption reaction rate depends on two parameters, which might be the sorbate concentration and sorbent dosage. The Langmuir isotherm model was the best one for the description of sorption of Cr(VI) onto bone char and bio-char.

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Georges, George Tharwat. "Novel Characteristics of Murine Bone Marrow-Derived Macrophages and Human Macrophage-Like Cells." VCU Scholars Compass, 2006. http://scholarscompass.vcu.edu/etd/932.

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These studies provide evidence for novel properties of macrophages derived from bone marrow stem cells. In study 1, treatment of activated mouse bone marrow-derived macrophages (BMM) with either catecholamine synthesis inhibitors (α-methyl-para-tyrosine and fusaric acid) or the β2 adrenergic receptor antagonist ICI 118,551 demonstrated that BMM produce catecholamines. The catecholamines modulated macrophage cytokine production through autocrine actions on adrenergic receptors. In study II, undifferentiated human bone marrow cells were incubated in 30% mouse L929 fibroblast conditioned medium and generated adherent cells within three days. The cells were clearly identifiable as macrophages based on surface proteins and phagocytic activity but produced only low levels of the cytokines tumor necrosis factor-α and interleukin-lβ. Cytokine production did not increase in response to the bacterial endotoxin lipopolysaccharide (LPS). Generation of these macrophage-like cells was not repeatable with other samples of human bone marrow, but the cells continue to proliferate in cell culture and will be investigated further in future studies.

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Abdallah, Sadoon Mushrif. "Bonding mechanisms and strength of hooked-end steel fibre reinforced cementitious composites." Thesis, Brunel University, 2017. http://bura.brunel.ac.uk/handle/2438/15827.

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Concrete is a strong material as to its compressive strength. However, it is a material with a low tensile and shear strength, and brittleness at failure. Concrete has to be reinforced with appropriate materials. Steel fibre is one of the most common materials currently being used to develop reinforced concrete, which may replace partially or completely conventional steel reinforcement. Successful reinforcement of concrete composite is closely related to the bond characteristics between the reinforcing fibre and matrix. The effective utilisation of steel fibre reinforced concrete (SFRC) requires in-depth and detailed understanding of bonding mechanisms governing the tensile behaviour. In response to this demand, this study embraced two main areas: understanding the reinforcing mechanisms of fibres in SFRC and material's post-cracking behaviour. Comprehensive experimental and theoretical programmes have therefore been developed: the experimental work is subdivided into three parts. The first part was to investigate the effect of various physical parameters, such as fibre characteristics (i.e. geometry, inclination angle, embedded length, diameter and tensile strength) and matrix strength which controls the pull-out behaviour of steel fibres. The second part is concerned with the assessment of the bond mechanisms of straight and hooked end fibres after exposure to elevated temperatures and varying matrix strength. The third part is devoted to gain further insight on the bond mechanisms governing the post-cracking behaviour through uniaxial and bending tests. It was found that the varying hook geometry and matrix strength each had a major influence on the pull-out response of hooked end fibres. As the number of the hook's bends increased, the mechanical anchorage provided by fibre resulted in significant improvement of mechanical properties of SFRC. The reduction in bond strength at elevated temperatures is found to be strongly related to the degradation in properties of the constituent materials, i.e. the fibre and concrete. The most effective combination of matrix strength and fibre geometry was found to be as follows: 3DH (single bend) fibre with normal-medium strength matrix, 4DH (double bend) fibre with high strength matrix and 5DH (triple bend) fibre with ultra-high performance matrix. Two analytical models to predict the pull-out behaviour of hooked end fibres were developed. Both models were able to predict the pull-out response of SFRC made from a variety of fibre and matrix characteristics at ambient temperature. This work has established a comprehensive database to illustrate the bonding mechanisms of SFRC and anchorage strengthening of various hooked end fibres, and this should contribute towards an increasing interest and growing number of structural applications of SFRC in construction.

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Dreyfus, Deborah Elizabeth. "Characteristics associated with bone mineral density screening in a sample of adults with intellectual disabilities." Thesis, Boston University, 2012. https://hdl.handle.net/2144/32013.

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Thesis (M.S.)--Boston University
PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.
Adults with Intellectual Disability (ID) are at an elevated risk of osteoporosis based on lower peak bone mass and medical characteristics. However, there is little data as to how the medical characteristics affect screening or at what ages people are being screened. Methods: A secondary cross-sectional data analysis of was conducted of 4777 adults witl1 Intellectual Disability to determine characteristics associated with an elevated risk for osteoporosis and receipt of bone density screening. Hypotheses were that increasing age, use of antiseizure medication, living in a 24 hour residential setting, and receiving a flu vaccine increased the likelihood of screening. Bivariate analyses were initially performed, tl1en data were stratified by gender and logistic regressions were performed. Findings: 22.2% of the sample in this study received bone density screening. Bivariate odds ratios identified each of the hypothesized variables as significantly associated with receiving screening. Additionally, many of the covariates analyzed identified significant associations with receiving screening.Data were then stratified by gender and evaluated in a logistic regression. In men, increasing age, tl1e use of antiepileptic medication (adjusted odds ratio (OR) 1.5; 95% confidence interval (CI) 1.2-2.0), and receiving the flu vaccine (adjusted OR 1.5; 95% CI 1.2-2.0) were associated witl1 an increased likelihood of screening, controlling for confounding. Living in a 24 hour residential setting was not significantly associated with screening (adjusted OR 1.2; 95% CI 0.91-1.6). In women, increasing age, the use of antiepileptic medication (adjusted OR 1.5; 95% CI 1.2-1.9), receiving the flu vaccine (adjusted OR 1.4; 95% CI 1.1-1.8), and living in a 24 hour residential setting (adjusted OR 1.4; 95% CI 1.1 -1.8) were all significantly associated with receiving screening. A history of Down syndrome, noted to increase risk of osteoporosis, was associated with a decreased likehl1ood of screening (adjusted OR 0.67; 95% CI 0.4 7-0. 94) in women, although it was not a significant association in men. Conclusions: While most variables related to osteoporosis are associated with an increased likelihood of screening, screening rates among in adults witl1 ID were low. Additionally, men and women have differences in variables related to screening. Better education and improved awareness may increase rates.
2031-01-02

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Konečná, Kateřina. "Návrh pracovního bodu odstředivého čerpadla." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228305.

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Target of diploma thesis The Operating Point of the Centrifugal Pump was create program for analyze system of pumps, it would be an effective instrument at projection these systems. Program is divided into two parts: system characteristic and performance characteristic. Subject of this thesis is create pumps database, enter performance characteristics and succeeding working with them. Program enable regulation pump with change speed and cooperation two pumps, work in parallel or series. The result of program is project system of pumps on enter parameters with more economy work.

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Shu, Shan Shan Kate. "Identification of the characteristics of bone affected by Charcot osteoarthropathy and the role of the endocannabinoid system in human bone and osteoclasts." Thesis, University of Nottingham, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.580162.

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Introduction: The endocannabinoid signalling system has been implicated in a broad spectrum of pathological and physiological processes including the control of inflammation and pain. Recent pre-clinical studies have demonstrated the therapeutic potential of cannabis-based drugs in the treatment of inflammatory musculoskeletal conditions, including rheumatoid arthritis. Studies in rodent models suggest that the endocannabinoid system modulates bone remodelling, via actions at the cannabinoid CB1, CB2 receptors and the TRPVl ion channel. The effects of the endocannabinoid system in inflammatory processes and bone homeostasis suggest that they may impact on the pathogenesis of Charcot osteoarthropathy, a non-infective, chronic destructive condition of the bone initiated by neuro-traumatic stimuli, most prevalent in patients with diabetic peripheral neuropathy. Neuropathy-induced changes in the endocannabinoid system may contribute to bone breakdown in Charcot, dependent or independent of the RANKL/RANK/OPG signalling pathway which is known to regulate bone remodelling. The aims of this thesis were to quantify and compare the levels of endocannabinoids and components of the endocannabinoid receptor system in human trabecular bone from Charcot and non-Charcot subjects, to identify a functional endocannabinoid system in human osteoclasts in culture, and to determine the effect of TRPVl modulation on osteoclastogenesis. Methods: Bone biopsies and blood were taken from patients with Charcot osteoarthropathy or those undergoing elective foot surgery. Histological features of the Charcot and non-Charcot bone were compared following staining with haematoxylin. Plasma levels of the inflammatory marker, CRP, and bone turnover markers (ALP, CTx) were measured with routine biochemical analysis. Plasma levels of RANKL, OPGJ and inflammatory cytokines (TNFa, IL-l, IL-6, IL-7) were measured using enzyme-linked immunosorbent assay. Levels of endocannabinoids in plasma and bone were analysed by liquid chromatography-tandem mass spectrometry (LC- MS/MS). Osteoclasts were differentiated from U-937 cells (human leukaemic monocyte lymphoma cells) using TPA (O.Lpq/rr»). followed by calcitriol (10- BM) or TNFa (3ng/ml). Tartrate-resistant acid phosphatase (TRAP) staining and resorption of calcium phosphatase were used to identify mature osteoclasts. Components of the endocannabinoid system, together with osteoclast markers (TRAP, cathepsin K) and RANKL/OPG were detected at the mRNA level in human trabecular bone and osteoclasts with quantitative PCR. Modulation of ATP(lOOIJM)-induced calcium responses by CB1 and CB2 receptor agonists (ACEA (lIJM), JWH133 (3IJM), CP55940 (3IJM» were used to demonstrate the presence of functional cannabinoid receptors. Exposure of osteoclasts to the TRPVl receptor antagonist capsazepine (3IJM) and agonist AEA (lIJM) was used to study the role of TRPVl in osteoclastogenesis. Results: Histology of the Charcot bone showed a loss of bone microarchitecture, loss of marrow space and features of increased bone turnover. Higher levels of ALP, CTx and IL-6 were detected in Charcot plasma, compared to controls, indicating an inflammatory response and an increase in bone turnover. An increase in OPG level, but not RANKL was found in Charcot plasma. The endocannabinoids 2-AG, AEA and related compounds PEA and OEA were detected in human trabecular bone (not AEA) and plasma although no significant differences were evident between Charcot and control samples. Components of the endocannabinoid system, with the exception of CB2 receptors, were detected at the mRNA level in human trabecular bone. Lower levels of the endocannabinoid-related nuclear receptor PPARy (known to be anti-inflammatory) were found in Charcot bone compared to that of controls. Osteoclasts differentiated from U-937 cells showed positive TRAP staining, were multinucleated and calcium phosphate-resorbing from day 5 of culture. mRNA expression of components of the endocannabinoid system were significantly up-regulated with osteoclast maturation. The application of CB1/2 receptor agonists modified ATP-induced calcium responses in osteoclasts. Exposure of osteoclasts to capsazepine, but not AEA, Significantly attenuated the number of TRAP-positive osteoclasts. Effects of capsazepine were attenuated by AEA. Conclusion: Work in this thesis has confirmed the link between Charcot and an increase in bone turnover (increased ALP and CTx levels), and the presence of an inflammatory response (increased IL-6 levels). It also demonstrated the presence of active endocannabinoid signalling, in Charcot and non-Charcot trabecular bone, and osteoclasts. Marked histological changes were observed in Charcot bone. The lack of genetic data and the sporadic and rare nature of this condition renders it difficult to establish the mechanisms of the disease. Marked differences were seen in the effect of osteoclast maturation on the endocannabinoid system. Importantly, the process of osteoclastogenesis was seen to be halted by TRPVl channel inhibition suggesting that pharmacological interventions targeting TRPVl could be used in the control of osteoclastogenesis. These data add to the growing evidence that the endocannabinoid signalling system plays an important role in bone homeostasis, and that alterations in the components of this system may contribute to pathological conditions of the bone, such as osteoporosis, osteoarthritis, and Paget's disease.

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Kerschnitzki, Michael [Verfasser], Peter [Akademischer Betreuer] Fratzl, Franz [Akademischer Betreuer] Pfeiffer, and Norbert [Akademischer Betreuer] Koch. "Bone material characteristics influenced by osteocytes / Michael Kerschnitzki. Gutachter: Peter Fratzl ; Franz Pfeiffer ; Norbert Koch." Berlin : Humboldt Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2012. http://d-nb.info/1020871164/34.

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I-Fan, Liang, and 梁一凡. "Bond Characteristic of KMnO4." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/27295743467994166192.

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Lin, Kuan-Ju, and 林寬鋸. "Electron density distributions of some characteristic chemical bonds--H-Bonds, hypervalent sulfur bonds, chromium carbene bond and Rh-Rh Metal-Metal bond." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/19501586734036953443.

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Lin, Yun-Wei, and 林昀蔚. "The Characteristic of Convertible Bond in Reset Period." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/47142518828134667306.

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碩士
國立高雄第一科技大學
財務管理研究所
99
This study employs Vector Autoregressive Model (VAR) to examine the causality relationship between convertible bond and stocks in the periods of conversion-price reset and general non-reset. Logistic regression was applied to analyze the effect of causality relationship for different financial situations and corporate governance variables. Both the past literature and this study for the general non-reset period indicated that the price of convertible bond always fall behind the stock price of the issuing company. However, for the reset period the number of companies whose stock prices lead that of the convertible bond increased. The regression analysis results showed that in the reset period the investors would like to trade the convertible bond as the company achieves higher profits, better performance and growth potential and as the company reduces the conversion price. That presents the reversal phenomenon, that is, the CB return leads the stock return, based on the uprising liquidity and information transparency.

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Wu, Chun-Da, and 吳俊達. "A Study of Characteristic Analysis of Medium Voltage Breaker of Electromagnetic Actuator with Bond Graph Theory." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/rs29vx.

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碩士
國立臺北科技大學
電機工程系所
99
In this thesis, the target is analyzing the characteristic of electromagnetic actuator for circuit breaker with bond graph method. Bond graph method, which is particularly useful in the description of multi-energy dynamic system of electromagnetic actuator, it contains electrical, magnetic and mechanical field. By observing the energy transfers in the bond graph model and physical structure can provide a way to design and revise model. Bond graph method could convert into Simulink model and validated by comparing measured data with simulation result. Based on the feature of combining with multi-energy from bond graph method, a magnetic time constant been proposed, it can provide a way to design. Finally, in order to improve the speed of electromagnetic actuator, four scheme of model revision was proposed.

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Alavi-Fard, Mehdi. "Bond characteristics of high strength concrete /." 1999.

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Mitchell, David William. "Bond characteristics of high strength lightweight concrete /." 2001.

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Feng, Wei-Shiang, and 馮韋翔. "How Company Financial Characteristics Affect Convertible Bond Design." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/56821111279622185072.

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碩士
國立臺灣大學
國際企業學研究所
99
According to the pecking order theory, business financing cost from high to low are new stock issued, debt financing and internal earning. Convertible bond is one of the debt financing and it owns debt and equity characteristics simultaneously. We use Black-Scholes formula to separate convertible bonds into debt-like and equity-like debt. Then, we apply classified convertible bonds to regress with financial characteristics of other business which hadn’t issue convertible bond ever. The results show business which are large firm size, low slack, high current asset ratio, high market to book value, high growth in asset change, high volatility and low stock return propensity to issue debt-like CB. There are similar results in equity-like CB, however, the stock return isn’t significant. We also considered the specialty of Taiwan capital market and bifurcated into tech and non-tech industry. The study reveals equity-like CB has more significant variables than debt-like CB. Last but not least, we add market condition into our regression model. Firm size and stock return variables have significant in market condition regression. Furthermore, we mixed market condition and industry different together. The result suggests no matter in hot or cold market. CB issued by high tech industry have less significant. There are more significant variables in non-tech industry during cold market. We believe that shows investors will highly concerned the implicit value of embedded option during cold market.

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