Dissertations / Theses: 'High-density'

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Wong, Man Kin. "High-density courtyard houses." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ63566.pdf.

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Wu, Di. "High Density Residential Design." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/76679.

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Massive migration is one the most significant phenomena of China's urbanization. In the thirty years since the "Reform and Open Up" policy began, Guangzhou has experienced economic growth and urban expansion and attracted a vast number of migrants. Seen as the product of the rapid urbanization, urban villages accommodate the majority of migrants by providing low-rent housing, but at the same time cause many social problems. This thesis aim at improving the migrants' standard of living, helping them gradually integrate into the city, and enhancing the potential for social interactions in the neighborhood.
Master of Architecture

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Ucar, Egemen. "Ternary Nanocomposites Of High Density, Linear Low Density And Low Density Polyethylenes." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608446/index.pdf.

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In this study, the effects of organoclay loading, compatibilizer loading and polyethylene type on the morphology, rheology, thermal properties and mechanical properties of polyethylene/compatibilizer/organoclay nanocomposites were investigated. As compatibilizer, terpolymer of ethylene-methacrylate-glycidyl methacrylate (Lotader®
AX8900), as organoclay Cloisite®
15A were used. All samples were prepared by a co-rotating twin screw extruder, followed by injection molding. Considering ternary nanocomposites, highest impact strength results were obtained with 10% compatibilizer plus 2% organoclay
highest yield stress, elastic modulus, flexural strength, flexural modulus were obtained with 5% compatibilizer plus 4-6% organoclay. DSC data indicated that addition of organoclay and compatibilizer did not change the melting point remarkably
on the other hand it affected the crystallinity. The organoclay used had no nucleation effect on polyethylene, and the compatibilizer decreased the crystallinity of the matrix. X-ray diffraction showed that in all ternary nanocomposites and in binary nanocomposite of high density polyethylene with organoclay, layer separation associated with intercalation of the clay structure occurred,. The highest increase of interlayer gallery spacing was obtained with 10% compatibilizer plus 2% organoclay, which were 25%, 28% and 27% for HDPE, LLDPE and LDPE matrices respectively.

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Zhou, Jinghai. "High Frequency, High Current Density Voltage Regulators." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/27268.

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As a very special DC-DC converter, VRM (Voltage Regulator Module) design must follow the fast-developing trend of microprocessors. The design challenges are the high current, high di/dt, and stringent load-line requirement. When the energy is transferred from the input of a VRM, through the VRM, then through the power delivery path to the processor, it needs sufficient capacitors to relay this energy. The capacitorsâ number appears to be unrealistically large if we follow todayâ s approach for the future processors. High frequency VRM with high control bandwidth can solve this problem, however, the degradation of efficiency makes the conventional buck converter and the hard-switching isolated topologies incapable of operating at higher frequency. The research goal is to develop novel means that can help a high-output- current VRM run efficiently at high frequency. A novel Complementary Controlled Bridge (CCB) self-driven concept is proposed. With the proposed self-driven scheme, the combination of the ZVS technique and the self-driven technique recycles the gate driving energy by making use of the input capacitor of the secondary- side synchronous rectifier (SR) as the snubber capacitor of the primary-side switches. Compared to the external driver, the proposed converter can save driving loss and synchronous rectifier body diode conduction loss. Additionally, compared to the existing level-shifted self-driven scheme for bridge-type symmetrical topologies, its gate signal ringing is small and suitable for high-frequency applications. Although the CCB self-driven VRM reduces the switching frequency-related losses significantly, the conduction loss is still high. Inspired by the current-doubler concept, a novel ZVS current-tripler DC-DC converter is proposed in this work. By utilizing more SR devices to share the current during the freewheeling period, the SR conduction loss is reduced. The current-tripler DC-DC converter has a delta/delta connected transformer that can be implemented with integrated magnetics. The transformer then becomes an integrated magnetic with distributed windings, which is preferred in high current applications. The current-tripler DC-DC converter in fact meets the requirements for the CCB self-driven scheme. The two concepts are then combined with an integrated gate drive transformer. The proposed CCB self-driven concept and current-tripler concept can both be applied to the 12V non-isolated VRMs. The proposed topology is basically a buck-derived soft-switching topology with duty cycle extension and SR device self-driven capabilities. Because there is no isolation requirement, the SR gate driving becomes so simple that the voltage at the complementary controlled bridge can be used to directly drive the SR gate. Both the gate driving loss and the SR body diode conduction loss are reduced. The proposed circuit achieves similar overall efficiency to a conventional 300kHz buck converter running at 1MHz. All the circuits proposed in this dissertation can use coupling inductors to improve both the steady-state efficiency and dynamic performances. The essence of the coupling inductors concept is to provide different equivalent inductances for the steady state and the transient. Moreover, when a current loop becomes necessary to achieve proper current sharing among phases, the current loop sample hold effect will make it difficult to push the bandwidth. The sample hold effect is alleviated by the coupling inductors concept. A small-signal model is proposed to study the system dynamic performance difference with different coupling inductor designs. As the verification, the coupling concept is applied to the 12V non-isolated CCB self-driven VRM and the bandwidth as high as one third of the switching frequency is achieved, which means a significant output capacitor reduction.
Ph. D.

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Abraham, Jose P. "Density dynamics: a holistic understanding of high density environments." Kansas State University, 2014. http://hdl.handle.net/2097/17308.

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Master of Regional and Community Planning
Department of Landscape Architecture/Regional and Community Planning
Jason Brody
Today, achieving higher residential densities is an integral part of most discussions on concepts such as sustainability, placemaking, smart growth and new urbanism. It is argued that high density environments can potentially improve quality of life through a range of social benefits. In attempting to achieve these benefits, often times, developments that provide more than a certain number of dwelling units are considered desirable and successful high-density developments. However, understanding high residential density merely in terms of an increase in the number of dwelling units over an area of development might not help realize meaningful social benefits; in fact it could result in problems such as parking constraints, increased vehicular traffic, crowding, and eventually abandonment. This implies a dilemma of understanding high density environments holistically. Using literature review and design exploration as two key research methods, this project aims at resolving this dilemma by presenting a holistic understanding of desirable high-density environments. The research works on the idea that high densities are a matter of design and performance. Through synthesis of literature review and explorative design findings, this research focuses on the qualitative aspects of high density environments that make them meaningful and desirable. Through synthesis of literature review and design findings, the research finds that desirable high density environments should (a) Be Physically Compact; (b) Support Urbanity; and (c) Offer Livability and Sense of Place. These three qualitative aspects of high density environments are critical in determining how well such environments perform. The research further proposes eight meaningful goals and seventeen specific guidelines to achieve aforementioned three qualities that influence the performance of high density developments. In addition to these principles and guidelines, opportunities and challenges posed by explorative design exercises also allows identifying certain supplementary guidelines necessary to strengthen the framework. Together, these findings result in a theoretical framework that may be used as an effective design and evaluation tool in considering high density environments. This framework is named “Density Dynamics” to signify various morphological and socio-economic dynamics involved in a holistic understanding of high density environments.

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Schoeck, Kenneth O. "HIGH SPEED DOUBLE DENSITY RECORDING." International Foundation for Telemetering, 1986. http://hdl.handle.net/10150/615564.

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International Telemetering Conference Proceedings / October 13-16, 1986 / Riviera Hotel, Las Vegas, Nevada
The Western Space and Missile Center has requirements to record high bit rate PCM telemetry data in both predetection and post-detection formats. Recording time is inadequate using standard wideband instrumentation magnetic tape recorder/reproducers. Using double density recording technology, recording time can be doubled, but results in some degradation in recorder performance. This paper discusses the effects of double density recording on recorder performance and on the quality of high bit rate telemetry data.

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Royse, David M. "High density ammonia storage materials." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:2ccbf0d0-2fa7-4508-9544-565e47bfaddc.

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This Thesis considers the use of solid-state metal ammines as ammonia storage materials and endeavours to understand these materials on a fundamental chemical level. The ammines of LiBH₄, MgCl₂, MgBr₂, MgI₂ and Mg(BH₄)₂, are investigated. The structures of lithium borohydride ammines, Li(NH₃)_nBH₄ with n = 1, 2, 3 and 4 are solved using X-ray and neutron diffraction, vibrational spectroscopy, nuclear magnetic resonance, and first-principles calculations. The reversibility, bonding and ammonia storage properties of this system are discussed, and investigated using gravimetric analysis and vibrational spectroscopy. The ammines of magnesium halides are investigated using X-ray and neutron powder diffraction, gravimetric techniques, nuclear magnetic resonance, first-principles calculations and vibrational spectroscopy. Their disordered structures, bonding, and decomposition are discussed, and the trends in their properties are used to interpret the properties of other ammines. The ammines of magnesium borohydride are investigated using X-ray and neutron powder diffraction, gravimetric techniques, first-principles calculations and vibrational spectroscopy. The structure, decomposition and reversibility of Mg(NH₃)₆(BH₄)₂ as an ammonia store are presented. Throughout the Thesis and at the end of each Chapter the possibility of using these ammines as solid-state ammonia stores is discussed.

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Kirichenko, E., and E. Belovol. "High-energy-density sugar biobattery." Thesis, Sumy State University, 2014. http://essuir.sumdu.edu.ua/handle/123456789/45213.

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The rapidly growing demand for powering portable electronic devices is driving the development of better batteries with features such as enhanced energy-storage densities, high levels of safety, biodegradability and small environmental footprints. The lithium-ion battery is often the system of choice because it offers a high energy density, has a flexible and light-weight design and has a longer lifespan than comparable battery technologies. The widespread use of metal-catalysed batteries also raises many concerns, primarily related to safety, toxic metal pollution and the availability of costly, limited, irreplaceable or rare metal resources.

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Li, Yanchao. "High Power Density and High Efficiency DC-DC Converters." Diss., North Dakota State University, 2018. https://hdl.handle.net/10365/28879.

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Shen, Wei. "Design of High-density Transformers for High-frequency High-power Converters." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/28280.

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Moore's Law has been used to describe and predict the blossom of IC industries, so increasing the data density is clearly the ultimate goal of all technological development. If the power density of power electronics converters can be analogized to the data density of IC's, then power density is a critical indicator and inherent driving force to the development of power electronics. Increasing the power density while reducing or keeping the cost would allow power electronics to be used in more applications. One of the design challenges of the high-density power converter design is to have high-density magnetic components which are usually the most bulky parts in a converter. Increasing the switching frequency to shrink the passive component size is the biggest contribution towards increasing power density. However, two factors, losses and parasitics, loom and compromise the effect. Losses of high-frequency magnetic components are complicated due to the eddy current effect in magnetic cores and copper windings. Parasitics of magnetic components, including leakage inductances and winding capacitances, can significantly change converter behavior. Therefore, modeling loss and parasitic mechanism and control them for certain design are major challenges and need to be explored extensively. In this dissertation, the abovementioned issues of high-frequency transformers are explored, particularly in regards to high-power converter applications. Loss calculations accommodating resonant operating waveform and Litz wire windings are explored. Leakage inductance modeling for large-number-of-stand Litz wire windings is proposed. The optimal design procedure based on the models is developed.
Ph. D.

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Dittes, Frank-Michael, Ingrid Rotter, and Erich Sobeslavsky. "Resonance phenomena at high level density." Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-32256.

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Merriam, Deborah Lee. "Tyrosyl radical-oxidized high-density lipoproteins." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ28967.pdf.

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Varma, Ambrish Kant. "COMPUTER AIDED TOOLSFORSEAMLESS HIGH DENSITY INTERCONNECTS." NCSU, 2001. http://www.lib.ncsu.edu/theses/available/etd-20010410-171850.

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Varma, Ambrish Kant. Computer - Aided Tools for Seamless High DensityInterconnects. (Under the direction of Paul D. Franzon)
This thesis presents the tool-set designed to demonstrate the possibility of using theCadence tools to design, verify and extract circuitry on the substrate along with theon-chip design. This circuitry could be an inter-chip connection that connects twodifferent chips or an intra-chip connection where a long interconnect is taken off fromthe active area of the chip to the substrate and back on to the same chip.
To be able to do this task, the work for this project is broadly classified into fourdifferent categories. These are writing
The technology file and the display.drf file The Design Rule Check deck The Layout Verses Schematic deckAfter having completed the above-mentioned tasks, the tool-set was also tested andimplemented on a circuit.

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Sivaprakasam, Mohanasankar. "High density microstimulators for retinal prosthesis /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2006. http://uclibs.org/PID/11984.

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Chan, Wun-cheung Katherine. "Sustainable development and high density living." Click to view the E-thesis via HKU Scholars Hub, 2006. http://lookup.lib.hku.hk/lookup/bib/B37937522.

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Berkowitz, Evan Scott. "Some novel phenomena at high density." Thesis, University of Maryland, College Park, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3590598.

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Astrophysical environments probe matter in ways impossible on Earth. In particular, matter in compact objects are extraordinarily dense. In this thesis we discuss two phenomena that may occur at high density.

First, we study toroidal topological solitons called vortons, which can occur in the kaon-condensed color-flavor-locked phase of high-density quark matter, a candidate phase for the core of some neutron stars. We show that vortons have a large radius compared to their thickness if their electrical charge is on the order of 10⁴ times the fundamental charge. We show that shielding of electric fields by electrons dramatically reduces the size of a vorton.

Second, we study an unusual phase of degenerate electrons and nonrelativistic Bose-condensed helium nuclei that may exist in helium white dwarfs. We show that this phase supports a previously-unknown gapless mode, known as the half-sound, that radically alters the material's specific heat, and can annihilate into neutrinos. We provide evidence that this neutrino radiation is negligible compared to the star's surface photoemission.

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Buchman, Susan. "High-Dimensional Adaptive Basis Density Estimation." Research Showcase @ CMU, 2011. http://repository.cmu.edu/dissertations/169.

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In the realm of high-dimensional statistics, regression and classification have received much attention, while density estimation has lagged behind. Yet there are compelling scientific questions which can only be addressed via density estimation using high-dimensional data, such as the paths of North Atlantic tropical cyclones. If we cast each track as a single high-dimensional data point, density estimation allows us to answer such questions via integration or Monte Carlo methods. In this dissertation, I present three new methods for estimating densities and intensities for high-dimensional data, all of which rely on a technique called diffusion maps. This technique constructs a mapping for high-dimensional, complex data into a low-dimensional space, providing a new basis that can be used in conjunction with traditional density estimation methods. Furthermore, I propose a reordering of importance sampling in the high-dimensional setting. Traditional importance sampling estimates high-dimensional integrals with the aid of an instrumental distribution chosen specifically to minimize the variance of the estimator. In many applications, the integral of interest is with respect to an estimated density. I argue that in the high-dimensional realm, performance can be improved by reversing the procedure: instead of estimating a density and then selecting an appropriate instrumental distribution, begin with the instrumental distribution and estimate the density with respect to it directly. The variance reduction follows from the improved density estimate. Lastly, I present some initial results in using climatic predictors such as sea surface temperature as spatial covariates in point process estimation.

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Mistree, Behram Farrokh Thomas. "A flexible high-density sensor network." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/46015.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.
Includes bibliographical references (p. 171-174).
This thesis explores building and deploying a scalable electronic sensate skin that was designed as a dense sensor network. Our skin is built from small (1" x 1") rigid circuit boards attached to their neighbors with flexible interconnects. Each boardcontained an embedded processor together with a suite of thirteen sensors, providing dense, multimodal capture of proximate and contact phenomena. In addition to the design of the physical system, this thesis develops protocols for internode communication (both neighbor-neighbor and global), and power-efficient wake-on-phenomena operation. The system was rigorously tested with an array of up to 4x3 nodes subject to a variety of sensor stimuli. Although there were some robustness issues in the final design (particularly in the wired interconnects, which were not the focus of this thesis work), the skin that we developed showed good flexibility for a prototype, ran quickly and efficiently, and could detect and respond to a variety of stimuli.
by Behram Farrokh Thomas Mistree.
M.Eng.

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Dittes, Frank-Michael, Ingrid Rotter, and Erich Sobeslavsky. "Resonance phenomena at high level density." Forschungszentrum Rossendorf, 1994. https://hzdr.qucosa.de/id/qucosa%3A22052.

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Londoño, Ceballos Mauricio. "High-Density Polyethylene/Peanut Shell Biocomposites." Thesis, University of North Texas, 2014. https://digital.library.unt.edu/ark:/67531/metadc700037/.

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A recent trend in the development of renewable and biodegradable materials has led to the development of composites from renewal sources such as natural fibers. This agricultural activity generates a large amount of waste in the form of peanut shells. The motivation for this research is based on the utilization of peanut shells as a viable source for the manufacture of biocomposites. High-density polyethylene (HDPE) is a plastic largely used in the industry due to its durability, high strength to density ratio, and thermal stability. This research focuses in the mechanical and thermal properties of HDPE/peanut shell composites of different qualities and compositions. The samples obtained were subjected to dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), and mechanical tensile strength tests. TO prepare the samples for analysis, the peanut shells were separated into different mesh sizes and then mixed with HDPE at different concentrations. The results showed that samples with fiber size number 10 exhibited superior strength modulus of 1.65 GPa versus results for HDPE alone at 1.32 GPa. The analysis from the previous experiments helped to determine that the fiber size number 10 at 5%wt. ratio in HDPE provides the most optimal mechanical and thermal results. From tensile tests the highest modulus of elasticity of 1.33 GPa was achieved from the samples of peanut shells size number 10 in HDPE at 20%wt. ratio, while the results for HDPE alone were only of 0.8 GPa. The results proved the hypothesis that the addition of peanut shells to HDPE enhances both the thermal and mechanical properties of the composite.

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Wang, Hui. "Extended homozygosity in high density genotyping." Diss., Restricted to subscribing institutions, 2006. http://proquest.umi.com/pqdweb?did=1276395171&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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Sowers, Gerald Wayne. "Structure of high-density wall plasmas." Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/186244.

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Wall plasmas, plasmas in contact with a solid wall, are studied in two basic cases. The first is a linear theta-pinch. In this geometry the motion of the plasma along the field lines and the transfer of heat along the field lines is investigated using a transient hydrodynamic heat flow model and a steady state heat flow model. Good agreement is found with experimental results on the Scylla IV-P linear theta pinch. Results of the stationary model are used to estimate linear fusion reactor lengths. Results are that linear fusion reactors would be shorter for low atomic number (Z) end walls, but have higher linear power levels (power per unit length) for high Z end walls. The second case is a stationary solution of the structure of a plasma in contact with a diverter or limiter in a tokamak. This geometry is investigated to determine relationships between plasma density, temperature and the velocity of plasma flow toward the diverter. Solutions are found and sensitivities are presented.

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Meissner, Kenith Erwin II. "High-density plasma dynamics in semiconductors." Diss., The University of Arizona, 1994. http://hdl.handle.net/10150/186629.

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This dissertation presents a study of high density plasma dynamics in semiconductors. Chapter 1 serves as an introduction and presents the basics of how we will use optical nonlinearities in the study of a high density plasma. Chapter 2 develops the necessary femtosecond laser system and techniques utilized in this investigation. The basics of our colliding pulse modelocked femtosecond laser system are presented. A variety of data acquisition systems are also outlined and discussed. A detailed description of our method of chirp measurement and correction rounds out the chapter. Chapter 3 presents a study of plasma dynamics in type I and type II GaAs multiple quantum well samples. First, the samples are compared in the quasi-equilibrium regime. The transfer of carriers from the wells to the barriers in the type II sample is found to profoundly affect the optical nonlinearities. A many-body theory calculation of these nonlinearities is then presented. We also utilize the unique properties of the type II structure to study the picosecond dynamics of a one component (hole) plasma. Finally, the possibility of transient gain in the type II structure is explored and discussed. Chapter 4 describes an investigation into the gain dynamics in an optically inverted semiconductor. Spectral hole burning is observed throughout the gain region, and the dynamics of the hole burning are shown. Since this system is highly inhomogeneously broadened, these results are first modeled by a group of noninteracting, inhomogeneously broadened, two level transitions. This model permits simple insight into the dynamics, but does not do a complete job of modeling the results. So, a full many-body treatment is included to more completely describe the experiment. Chapter 5 presents a study of the dephasing time through the gain region and into the absorption region of an optically excited GaAs multiple quantum well sample. Both spectral and temporal methods for measuring the dephasing time are utilized. A distinct maximum of the dephasing time is observed at the transparency point. A many-body theory calculating the carrier-carrier scattering rate is presented to explain this maximum.

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Santhanam, Babu. "High density culture of Nitrosomonas and Nitrobacter /." St. Lucia, Qld, 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17359.pdf.

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Kim, Hyea. "High energy density direct methanol fuel cells." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37106.

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The goal of this dissertation was to create a new class of DMFC targeted at high energy density and low loss for small electronic devices. In order for the DMFC to efficiently use all its fuel, with a minimum of balance of plant, a low-loss proton exchange membrane was required. Moderate conductivity and ultra low methanol permeability were needed. Fuel loss is the dominant loss mechanism for low power systems. By replacing the polymer membrane with an inorganic glass membrane, the methanol permeability was reduced, leading to low fuel loss. In order to achieve steady state performance, a compliant, chemically stable electrode structure was investigated. An anode electrode structure to minimize the fuel loss was studied, so as to further increase the fuel cell efficiency. Inorganic proton conducting membranes and electrodes have been made through a sol-gel process. To achieve higher voltage and power, multiple fuel cells can be connected in series in a stack. For the limited volume allowed for the small electronic devices, a noble, compact DMFC stack was designed. Using an ADMFC with a traditional DMFC including PEM, twice higher voltage was achieved by sharing one methanol fuel tank. Since the current ADMFC technology is not as mature as the traditional DMFCs with PEM, the improvement was accomplished to achieve higher performance from ADMFC. The ultimate goal of this study was to develop a DMFC system with high energy density, high energy efficiency, longer-life and lower-cost for low power systems.

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Breznan, Dalibor. "High-density lipoprotein metabolism in the kidney." Thesis, University of Ottawa (Canada), 2002. http://hdl.handle.net/10393/6120.

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The kidney is believed to play a major role in the clearance and re-absorption of high density lipoprotein (HDL) particles from the blood. Experiments were undertaken to explore the specific sites of renal HDL metabolism in vivo and to investigate in vitro the factors that regulate the renal re-absorption of HDL by HKC-8 human proximal tubule (PT) cells. Perfusion of a rabbit renal artery with [3H]cholesteryl ester (CE) and 125I-protein labeled HDL particles showed that the kidneys are capable of filtering both apolipoprotein A-I (apoA-I) and whole HDL. A fluorescent microscopic study with the HKC-8 cells showed that the PT cells can bind and take up HDL particles. (Abstract shortened by UMI.)

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Liu, Weidong. "High density solids downflow gas-solids reactors." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0001/MQ42081.pdf.

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Timlett, Rose. "Recycling in high and medium density housing." Thesis, University of Southampton, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.543417.

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Zhang, Jingxuan, and 张静璇. "Therapeutic landscape in high-density urban environment." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B4754479X.

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Hong Kong’s compacted urban form brings about potential problems including mental illness. Meanwhile stressful life mainly originates from working pressure brought a lot of physical and mental problems for the people themselves and generating serious family and social problems. As more and more people start to aware mental health issue, the current mental health services system is no longer sustainable due to increasing number of patients. This thesis aims to excavate the potential for landscape to become element in healthcare delivery in the context of community as following: refine the definition of therapeutic landscape, define the scope of work, and identify components essential for therapeutic environment. Last but not least, dig out possible interpretation/physical form through set an example of a particular design introduce for a typical site. Therapeutic landscape which introduce to community recreation system will become a new approach to backup mental health service system as well provide people more convenient and broad healthcare service to cultivate healthy personality. Thus promote community organic development to become a thoughtful and institutional environment.
published_or_final_version
Architecture
Master
Master of Landscape Architecture

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Olsson, Robbie Stefan Ian. "High energy density physics in cluster media." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/18394.

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Gases comprised of atomic clusters have in the past been shown to exhibit extremely strong absorption of high-intensity laser pulses. By using this target medium, it is possible to use laser systems with only modest energies to create High Energy Density Plasmas. Not only are the plasmas created in this way of interest in themselves, but when properly designed, these experiments can be used as a platform for Laboratory Astrophysics studies of radiative blast waves. This thesis describes experiments which investigate the evolution of radiative blast waves, the interaction of relativistic laser pulses with large atomic clusters and the nature of the post laser-cluster interaction upstream medium into which the shock propagates. Experiments were carried out to diagnose the properties of the upstream medium into which radiative shocks launched by the laser-cluster interaction propagate. This experiment was conducted using the Blackett Laboratory Laser Consortium Nd:Glass laser system with a novel perpendicular heating beam geometry. By introducing a time delay between the perpendicular beams, it was possible to track the propagation of a ballistic cluster disassemble wave. This wave was shown to be the product of ~200 keV ions ejected by the initial laser cluster-interaction. Also discussed in this thesis are the results of the first laser-cluster experiment to be conducted on the Central Laser Facility's Astra-Gemini system. Here the interaction of large atomic clusters with relativistic laser pulses is investigated. X-Ray pinhole camera images have been captured of the early time plasma created by the laser-clusters interaction. For the first time the absorption properties of large atomic clusters irradiated by a femtosecond high energy, ~14 J, laser pulse have been studied. Furthermore, the temporal evolution of radiative blast waves launched from the laser-cluster interaction is described. In the past the Vulcan laser system at RAL was used to launch blast waves which displayed velocity domain oscillations driven by the radiation emitted by the blast wave. This instability has again been observed in the work reported here and the threshold for onset has been investigated.

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Yeow, Eddie Y. "Design of high-density dc/dc converters." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/41524.

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Zero- Voltage-Switching Multi-Resonant-Converter (ZVS-MRC) techniques are applied with hybrid microelectronics fabrication technologies to design and implement efficient, high-density (>50 W/in³) dc/dc converters. A low-profile high-density power stage of a 25 W dc/dc flyback ZVS-MRC is designed and built, and experimental results are shown. A high-density control circuit for a 50 W forward ZVS-MRC is designed using an integrated controller. This circuit is implemented into the high-density power stage previously designed by Tabisz and Lee to attain an overall converter power density of above 80 W/in³. A low-profile interleaved winding structure, fabricated by laminating copper-on-polyamide, for the transformer in the 50 W ZVS-MRC is introduced. Finite element analysis is performed to show the advantages gained with this structure.
Master of Science

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Eriksson, Olle. "Modeling Information Transfer in High-Density Crowds." Thesis, Uppsala universitet, Tillämpad matematik och statistik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-355371.

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Moon, John W. Jr, and Don Slack. "Consumptive Water Use in High Density Apples." College of Agriculture, University of Arizona (Tucson, AZ), 1990. http://hdl.handle.net/10150/215716.

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Liu, Yushi. "Low Profile, High Power Density and High Efficiency DC-DC Converters." Thesis, University of Colorado at Boulder, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10980034.

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Due to the ever decreasing thickness and increasing battery size of modern cellphones, battery chargers inside cellphones are required to meet increasingly stringent power density requirements, including small printed circuit board (PCB) area and component height. This thesis is focused on low-profile, high-power-density, and high-efficiency dc-dc converters for battery charging applications.

This thesis investigates five topologies, including ZVS-QSW buck converter, three-level buck converter, four-level buck converter, a resonant switched capacitor converter, and a new reconfigurable hybrid switched capacitor converter. The operation principle of each topology is described, and the advantages and disadvantages of each topology are analyzed and compared in terms of efficiency and power density. To accurately evaluate the performance of each topology, this thesis utilizes the augmented state-space modeling method that efficiently calculates the steady-state waveforms of a converter. To accurately predict losses, the dynamic on-resistance of GaN transistors and core loss of inductors have been modeled. Furthermore, a comprehensive optimization methodology is utilized to select circuit and component parameters.

For 2:1 conversation ratio application scenario, two prototypes using GaN transistors and low-voltage Silicon MOSFET have been designed, built and tested for an input voltage range of 5 V to 20 V, an output voltage range of 3 V to 4.2 V, and a maximum output current of 10 A. The prototype with GaN transistors (EPC2023) occupies a PCB area of 358 mm² with component height of 1 mm. To maximize efficiency, the converter is designed to achieve ZVS at light-to-medium loads, while sacrificing ZVS to reduce transistor conduction and inductor losses. This prototype converter achieves a peak efficiency of 98.5%. The prototype using low-voltage Silicon MOSFET (CPF03433) occupies a PCB area of 310 mm². A prototype of four-level buck converter with a PCB area of 410 mm², optimized for 3:1 conversion ratio, has also been built and tested. For extreme-power-density application, a prototype with a PCB area of 79.6 mm² and component height of 1 mm is built and tested. The prototype converter achieves a peak efficiency of 96.7% and a power density of 3230 W/in³.

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AlShehab, Ali Saeed. "Development and analysis of high-frequency, high-density PFC power conversion." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/106076.

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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2015.
Cataloged from PDF version of thesis. "September 2015."
Includes bibliographical references (pages 83-85).
This thesis explores the design of power converters that deliver isolated low-voltage dc output (~24V) and operate from "universal" ac input voltage (85 - 264 Vac RMS). It is important that these converters have good overall efficiency (~90-95%), and good ac line power factor (>0.9, and ideally >0.95) to better utilize the available energy. This thesis looks into achieving high efficiency, high power factor, low voltage stresses, and smaller component sizes by utilizing high frequency operation. The research focuses on component and subsystem evaluation, development and testing as a part of many-person research in this space. The thesis presents a literature based study on current PFC circuit designs and tradeoffs. It also introduces a specific PFC architecture, which provides a low dc output voltage drawing energy from a wide range ac input voltage while maintaining a high power factor. The architecture includes two stages: The first is a "Power Factor Correction" (PFC) which functions as an input stage drawing energy from a wide-range input current. It uses a resonant transition inverted (RTI) buck converter topology to step down the voltage from line voltage (85 - 264 Vac RMS) to around 72V. Furthermore, the inductor for the RTI buck is analyzed. The middle stage is an energy buffer to provide the required energy level for twice line frequency energy buffering and 20ms of energy hold up. The capacitor requirements, analysis, and selection are explored and developed. The second stage is a transformation and regulation stage which also provides electrical isolation between the ac input and dc output. The thesis also explores the use of available conventional high-density telecom "brick" converters as a second stage. In conclusion, the project explores the possibility of using a buck configuration for the PFC, sacrificing the ability to use high energy density 400V capacitors while gaining the advantage of using the high-density telecom brick converters and different output voltage options.
by Ali Saeed AlShehab.
M. Eng.

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Berdugo, Albert, and Martin Small. "HIGH SPEED ASYNCHRONOUS DATA MULTIPLEXER/ DEMULTIPLEXER FOR HIGH DENSITY DIGITAL RECORDERS." International Foundation for Telemetering, 1996. http://hdl.handle.net/10150/608366.

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International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California
Modern High Density Digital Recorders (HDDR) are ideal devices for the storage of large amounts of digital and/or wideband analog data. Ruggedized versions of these recorders are currently available and are supporting many military and commercial flight test applications. However, in certain cases, the storage format becomes very critical, e.g., when a large number of data types are involved, or when channel-to-channel correlation is critical, or when the original data source must be accurately recreated during post mission analysis. A properly designed storage format will not only preserve data quality, but will yield the maximum storage capacity and record time for any given recorder family or data type. This paper describes a multiplex/demultiplex technique that formats multiple high speed data sources into a single, common format for recording. The method is compatible with many popular commercial recorder standards such as DCRsi, VLDS, and DLT. Types of input data typically include PCM, wideband analog data, video, aircraft data buses, avionics, voice, time code, and many others. The described method preserves tight data correlation with minimal data overhead. The described technique supports full reconstruction of the original input signals during data playback. Output data correlation across channels is preserved for all types of data inputs. Simultaneous real-time data recording and reconstruction are also supported.

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Wang, Ruxi. "High Power Density and High Temperature Converter Design for Transportation Applications." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/28264.

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The continual development of high-power-density power electronic converters is driven particularly by modern transportation applications like electrical vehicles and more electric aircraft where the space and carrier capability is limited. However, there are several challenges related to transportation applications such as fault tolerance for safety concern, high temperature operation in extreme environments and more strict electromagnetic compatibility requirement. These challenges will increase difficulties for more electrical system adoption in the transportation applications. In this dissertation, comprehensive methodologies including more efficient energy storage solution, better power electronics devices capability, better packaging performance and more compact EMI filter design are analyzed and proposed for the goal of high power density converter design in transportation applications.
Ph. D.

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Ji, Shu. "High Frequency, High Power Density GaN-Based 3D Integrated POL Modules." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/19286.

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The non-isolated POL converters are widely used in computers, telecommunication systems, portable electronics, and many other applications. These converters are usually constructed using discrete components, and operated at a lower frequency around 200 ~ 600 kHz to achieve a decent efficiency at the middle of 80\'s%. The passive components, such as inductors and capacitors, are bulky, and they occupy a considerable foot-print. As the power demands increase for POL converters and the limited real estate of the mother board, the POL converters must be made significantly smaller than what they have demonstrated to date. To achieve these goals, two things have to happen simultaneously. The first is a significant increase in the switching frequency to reduce the size and weight of the inductors and capacitors. The second is to integrate passive components, especially magnetics, with active components to realize the needed power density.
Today, this concept has been demonstrated at a level less than 5A and a power density around 300-700W/in3 by using silicon-based power semiconductors. This might address the need of small hand-held equipment such as PDAs and smart phones. However, it is far from meeting the needs for applications, such as netbook, notebook, desk-top and server applications where tens and hundreds of amperes are needed.
After 30 years of silicon MOSFET development, the silicon has approached its theoretical limits. The recently emerged GaN transistors as a possible candidate to replace silicon devices in various power conversion applications. GaN devices are high electron mobility transistors (HEMT) and have higher band-gap, higher electron mobility, and higher electron velocity than silicon devices, and offer the potential benefits for high frequency power conversions. By implementing the GaN device, it is possible to build the POL converter that can achieve high frequency, high power density, and high efficiency at the same time. GaN technology is in its early stage; however, its significant gains are projected in the future. The first generation GaN devices can outperform the state-of-the-art silicon devices with superior FOM and packaging.
The objective of this work is to explore the design of high frequency, high power density 12 V input POL modules with GaN devices and the 3D integration technique. This work discusses the fundamental differences between the enhancement mode and depletion mode GaN transistors, the effect of parasitics on the performance of the high frequency GaN POL, the 3D technique to integrate the active layer with LTCC magnetic substrate, and the thermal design of a high density module using advanced substrates with improved thermal conductivity.
The hardware demonstrators are two 12 V to 1.2 V highly integrated 3D POL modules, the single phase 10 A module and two phase 20 A module, all built with depletion mode GaN transistors and low profile LTCC inductors.

Master of Science

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39

Rajasekaran, Nepolean. "A Nonlinear Constitutive Model for High Density Polyethylene at High Temperature." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1298041213.

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Sasaki, K., Y. Kawai, C. Suzuki, and K. Kadota. "Absolute density and reaction kinetics of fluorine atoms in high-density c-C_4F_8 plasmas." American Institute of Physics, 1998. http://hdl.handle.net/2237/7029.

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41

Sethi, Kanika. "High-density capacitor array fabrication on silicon substrates." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37259.

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System integration and miniaturization demands are driving integrated thin film capacitor technologies with ultra-high capacitance densities for power supply integrity and efficient power management. The emerging need for voltage conversion and noise-free power supply in bioelectronics and portable consumer products require ultra high-density capacitance of above 100 μF/cm2 with BDV 16-32 V ,independent capacitor array terminals and non-polar dielectrics. The aim of this research,therefore, is to explore a new silicon- compatible thin film nanoelectrode capacitor technology that can meet all these demands. The nanoelectrode capacitor paradigm has two unique advances. The first advance is to achieve ultra-high surface area thin film electrodes by sintering metallic particles directly on a silicon substrate at CMOS- compatible temperatures. The second advance of this study is to conformally- deposit medium permittivity dielectrics over such particulate nanoelectrodes using Atomic Layer Deposition (ALD) process. Thin film copper particle nanoelectrode with open-porous structure was achieved by choosing a suitable phosphate-ester dispersant, solvent and a sacrificial polymer for partial sintering of copper particles to provide a continuous high surface area electrode. Capacitors with conformal ALD alumina as the dielectric and Polyethylene dioxythiophene (PEDT) as the top electrode showed 30X enhancement in capacitance density for a 20-30 micron copper particulate bottom electrode and 150X enhancement of capacitance density for a 75 micron electrode. These samples were tested for their mechanical and electrical properties by using characterization techniques such as SEM, EDS, I-V and C-V plots. A capacitance density of 30 μF/cm2 was demonstrated using this approach. The technology is extensible to much higher capacitance densities with better porosity control, reduction in particle size and higher permittivity dielectrics.

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Karbasi, Ali. "Developing a High Density Pt/Alumina Hermetic Feedthrough." FIU Digital Commons, 2012. http://digitalcommons.fiu.edu/etd/667.

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Typically, hermetic feedthroughs for implantable devices, such as pacemakers, use a alumina ceramic insulator brazed to a platinum wire pin. This combination of material has a long history in implantable devices and has been approved by the FDA for implantable hermetic feedthroughs. The growing demand for increased input/output (I/O) hermetic feedthroughs for implantable neural stimulator applications could be addressed by developing a new, cofired platinum/alumina multilayer ceramic technology in a configuration that supports 300 plus I/Os, which is not commercially available. Seven platinum powders with different particle sizes were used to develop different conductive cofire inks to control the densification mismatch between platinum and alumina. Firing profile (ramp rate, burn- out and holding times) and firing atmosphere and concentrations (hydrogen (wet/dry), air, neutral, vacuum) were also optimized. Platinum and alumina exhibit the alloy formation reaction in a reduced atmosphere. Formation of any compound can increase the bonding of the metal/ceramic interface, resulting in enhanced hermeticity. The feedthrough fabricated in a reduced atmosphere demonstrated significantly superior performance than that of other atmospheres. A composite structure of tungsten/platinum ratios graded thru the via structure (pure W, 50/50 W/Pt, 80/20 Pt/W and pure Pt) exhibited the best performance in comparison to the performance of other materials used for ink metallization. Studies on the high temperature reaction of platinum and alumina, previously unreported, showed that, at low temperatures in reduced atmosphere, Pt3Al or Pt8Al21 with a tetragonal structure would be formed. Cubic Pt3Al is formed upon heating the sample to temperatures above 1350 °C. This cubic structure is the equilibrium state of Pt-Al alloy at high temperatures. The alumina dissolves into the platinum ink and is redeposited as a surface coating. This was observed on both cofired samples and pure platinum thin films coated on a 99.6 Wt% alumina and fired at 1550 °C. Different mechanisms are proposed to describe this behavior based on the size of the platinum particle.

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Veereswaran, Vasanthi. "High density lipoprotein intracellular metabolism in the kidney." Thesis, University of Ottawa (Canada), 2004. http://hdl.handle.net/10393/26792.

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Experiments were undertaken to evaluate the factors that control the re-absorptive salvage of high density lipoproteins (HDL) in the kidney. HDL is readily taken up at the apical surface of polarized human proximal tubule epithelial cells (HKC-8). HKC-8 cells do not degrade HDL apolipoproteins, but instead transport and re-secrete the lipoprotein from the opposite, basolateral surface. Only ∼10% of the HDL lipids taken up are re-secreted, while ∼60% of the internalized HDL proteins are re-secreted. The composition and charge of HDL directly affects their ability to be internalized and transported through HKC-8 cells. HDL-apolipoproteins stimulate the transport of HDL components to the basolateral surface, while HDL-lipids inhibit the process. Enrichment of HDL with phosphatidylinositol (PI) increases HDL negative charge and inhibits its transport and secretion from the basolateral surface. Enrichment with phosphatidylcholine (PC) decreases HDL charge and enhances the transcytosis of HDL. These results show that HDL composition and charge regulate the re-absorptive salvage of HDL apolipoproteins in the kidney by controlling the intracellular metabolism of this lipoprotein. Our data suggest that apical to basolateral transport within proximal tubule cells could serve to recover HDL from the glomerular filtrate and return it back to the circulation. A stimulation of this process may decrease the loss of HDL from the circulation and therefore be anti-atherogenic.

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44

Parmar, Harisinh, and h_arzoo@yahoo com. "Rheology Of Peroxide Modified Recycled High Density Polyethylene." RMIT University. Civil, Environmental and Chemical Engineering, 2008. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080724.164249.

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Consumption of plastics has increased exponentially, in line with the world's population. Not surprisingly this is reflected in enormous growth of the plastic industry especially during the last five decades. Commensurate with this, waste produced from plastics consumption has created a major environmental problem. Many types of waste disposal methods have been used all over the world so far, but all of them have disadvantages. Furthermore, some methods are responsible for the generation of green house gases and further contribution to global warming. Recently, reduction of green house gas emission has become a target of most industries. Plastic recycling and reuse breaks the cycle of endless production of virgin polymer and thus contributes to a net reduction of green house gas emission. Recycling of plastics should produce materials with improved properties to replace virgin plastics for a variety of applications. Improvement in the properties of recycled plastics can be achieved by blending with other plastics, by filler addition and by modification using free radical initiators. Introduction of the free radical initiator (organic peroxide) during reprocessing of the recycled plastics has been found to offer significant property improvements to the recycled materials. Extremely small amounts of a free radical initiator (typically ranging between 0.01 wt% to 0.2 wt%) is capable of enhancing the properties of the recycled plastics to a great extent. This project investigates the use of free radical initiators in the recycling of post consumer recycled high density polyethylene using reactive extrusion. Both molecular and rheological characterisation of recycled and reprocessed materials was carried out and this was followed by tensile testing of the modified materials to satisfy end use applications such as packaging and drainage piping. Post consumer recycled high density polyethylene (R-HDPE) resin and virgin high density polyethylene (V-HDPE) were reactively extruded with low concentrations of dicumyl peroxide (DCP) and 1, 3 1, 4 Bis (tert- butylperoxyisopropyl) Benzene (OP2) respectively in a twin screw extruder in order to produce modified materials with varying composition (0.0 wt%, 0.02 wt%, 0.05 wt%, 0.07 wt%, 0.10 wt% and 0.15 wt%) of both organic peroxides. Morphological characterisation using modulated differential scanning calorimetry (MDSC) demonstrated that there is a decrease in the crystallinity level for all the modified samples. Shear rheological tests were carried out to study the structure of the modified materials within the linear viscoelastic region. Viscoelastic parameters, such as storage modulus (G'), loss modulus (G

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45

Slatter, Tania Lee, and n/a. "Genetic contributors to high density lipoprotein cholesterol levels." University of Otago. Department of Biochemistry, 2007. http://adt.otago.ac.nz./public/adt-NZDU20070914.143900.

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Reduced high-density lipoprotein cholesterol (HDL-C) concentrations are a major risk factor for cardiovascular disease. Intense interest recently has been in identifying the genetic factors that contribute to an aberrant HDL-C phenotype. Finding genetic factors associated with low HDL-C concentrations in New Zealanders was the major aim of this study, with a similar analysis aimed at finding factors associated with high HDL-C concentrations included. The study began with an investigation of a New Zealand family with HDL-C deficiency. The proband had virtually no HDL-C, and was homozygous for an R1068H mutation in the ABCA1 gene. Nineteen relatives were recruited into the study, and an analysis aimed at finding the underlying cause for the disparate HDL-C phenotypes amongst H1068 carriers initiated. A further investigation into HDL-C levels aimed to find other genetic factors that contribute to HDL-C in New Zealanders. Subjects were selected from those taking part in the Otago Vascular Disease study, and placed into three groups based on their HDL-C lipid measurement: low (n=154), mid (n=105), and high (n=102) HDL-C. Mutations in ABCAI and the apolipoprotein AI gene (APOAI) were identified in subjects with low HDL-C. Polymorphisms in ABCA1 and APOAI were also investigated as contributors to HDL-C concentrations. Seventeen SNPs in functionally relevant regions were genotyped in the three HDL-C groups. Five single polymorphisms and one polymorphism haplotype showed a statistically significant association with HDL-C concentrations. The final analysis investigated plasma lipoprotein compositions in individuals with low HDL-C to identify if other lipoprotein abnormalities concurred. Individuals with HDL-C below 0.65 mmol/L were almost invariably associated with triglyceride-rich VLDL and/or triglyceride-rich LDL. This finding may have relevance for an increased atherosclerotic risk for those with low HDL-C.

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46

Issangya, Allan Shorusaeli. "Flow dynamics in high density circulating fluidized beds." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0034/NQ27168.pdf.

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47

Liang, Hui-Qi. "Remodelling of high density lipoproteins by plasma factors /." Title page, contents and summary only, 1996. http://web4.library.adelaide.edu.au/theses/09PH/09phl693.pdf.

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48

Khoshnaw, Fuad Mohamed Hassan. "Glass multilayer bonding for high density interconnect substrates." Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/6463.

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The aim of this research was the investigation of bonding borosilicate glass sheets, its trade mark CMZ, 100μm thickness, to create multilayer substrates capable of supporting high-density electrical interconnections. CMZ glass was chosen as it has a coefficient of thermal expansion that is close to that of silicon, thereby minimising thermal stresses in assemblies generated by manufacturing processes or service conditions. Two different methods of bonding the glass were used in this study; pressure assisted low temperature bonding (PALTB), and water glass bonding, using Sodium Trisilicate (Na2Si3O7) solution. These two bonding methods have already been applied in electronics manufacturing applications, such as silicon wafer bonding and multichip modules (MCMs). However, glass-to-glass bonding is a relatively new subject and this study is an attempt to standardise bonding processes. Additionally, the concept of using glass as a multilayer substrate provides a foundation for further exploration by other investigators. Initial tests that were carried out before standardising the procedures for these two methods showed that a two-stage bonding process provided optimum results. A preliminary stage commenced by placing the cleaned (using Decon 90 solution) samples in a vacuum oven for 15 minutes, then heating at 100oC for 1hr. The permanent stage was then achieved by heating the samples in a conventional oven at temperatures from 200 to 400oC, for different periods. At this stage, the main difference between the two methods was the application of pressure (1-2MPa) during heating of the PALTB samples. To evaluate the quality of the bonds, qualitative tests such as visual, optical microscope and dye penetrant were used. In addition, to estimate the strength and the rigidity of the interlayer bonds, two quantitative tests, comprising of deflection under cyclic stresses and crack opening were used. Thermal cycling and humidity tests were also used to assess resistance of the bonds to environmental effects. The results showed that heating to 100oC was insufficient to enhance the bonds, as occasionally a sudden increase of deflection was observed indicating slippage/delamination. These bonds were enhanced during the permanent bonding stage by heating to 300oC in PALTB, under a pressure of 1-2MPa. The crack-opening test showed that the delamination distances of the bonds in the permanent stage were lower than that for preliminary bonding in both bonding methods. The delamination distances from the crack opening tests were used to calculate the strain energy release rate (GIC) and fracture toughness (KIC) values of the interlayers. The results showed that the KIC values of the permanent PALTB and water glass interlayers were higher than 1MPa.m0.5, while the KIC value of the CMZ glass, determined by linear elastic fracture mechanics, was around 0.8MPa.m0.5. The optical observations revealed that the prepared bonded sheets did not delaminate or break after thermal cycling and humidity tests.

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Law, Cheuk-fung Jimmy, and 羅卓豐. "Asian Games Village: a High-Density Sports Complex." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31986572.

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50

Chung, Kang Ko. "Heteroatom-containing carbons for high energy density supercapacitor." Phd thesis, Universität Potsdam, 2013. http://opus.kobv.de/ubp/volltexte/2014/6982/.

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The supercapacitor is one of the most important energy storage devices as its construction allows for addressing many of the drawbacks related to batteries, but the low energy density of current systems is a major issue. In this doctoral dissertation, with a view to attaining high energy density supercapacitor systems that can be comparable to those for batteries, new heteroatom-containing carbons in the form of particles and three-dimensional films were investigated. A nitrogen-containing material, acrodam, was chosen as the carbon precursor due to the inexpensiveness, high carbonization yield, oligomerizability, etc. The carbon particles were prepared from acrodam together with caesium acetate as a meltable flux agent, and disclosed excellent properties in hydroquinone-loaded sulphuric acid electrolyte with high energy densities (up to 133.0 Wh kg–1) and sufficient cycle stabilities. These properties are already now comparable to those of batteries. Besides, conductive carbon three-dimensional films were fabricated using acrodam oligomer as the precursor by the inexpensive spin coating method. The films were found to be homogeneous, flat, void- and crack-free, and high conductivities (up to 334 S cm–1) could be obtained at the carbonization temperature of 1000 ºC. Furthermore, a porous carbon three-dimensional film could be formed using an organic template at the first attempt. This finding demonstrates the film’s potentiality for various applications such as supercapacitor electrode; the essential absence of contact resistance within the network should contribute to effective transportation of electron within the electrode. The progress made in this dissertation will open a new way to further enhancement of energy density for supercapacitor as well as other applications that exceeds the current properties.
Der Superkondensator ist einer der wichtigsten Energiespeicher da seine Konstruktion die Lösung vieler Nachteile von Batterien erlaubt. Allerdings weisen derzeitige Systeme noch zu geringe Energiedichten auf. Um Superkondensatoren mit Energiedichten vergleichbar zu Batterien zu ermöglichen, wurden in der vorliegenden Dissertation neue, heteroatomhaltige Kohlenstoffe in Form von Partikeln und Filmen untersucht. Aufgrund geringer Kosten, hohen Ausbeuten, Polymerisierbarkeit usw. wurde die stickstoffhaltige Substanz Acrodam als Kohlenstoffvorstufe verwendet. Die Kohlenstoffpartikel wurden ausgehend von Acrodam zusammen mit Cäsiumacetat als schmelzbares Flussmittel hergestellt und wiesen ausgezeichnete Eigenschaften in Hydrochinon geladenen Schwefelsäure-Elektrolyten mit hohen Energiedichten (bis zu 133,0 Wh kg–1) und guten Zyklusstabilitäten auf. Diese Eigenschaften sind bereits jetzt vergleichbar mit denen von Batterien. Weiterhin wurden unter Verwendung von Acrodamoligomeren als Vorstufe und mit Hilfe der kostengünstigen Rotationsbeschichtung leitfähige, dreidimensionale Kohlenstofffilme hergestellt. Bei einer Karbonisierungstemperatur von 1000 °C konnten die Materialien als homogene, flache, Hohlraum-und Riss-freie Filme erhalten werden, die eine hohe Leitfähigkeit (bis zu 334 S cm–1) aufwiesen. Darüber hinaus konnte mit einem organischen Templat ein dreidimensionaler, poröser Kohlenstoff geformt werden. Dies zeigt das Potential der Filme für verschiedene Anwendungen wie Superkondensatorelektroden; die Abwesenheit von Übergangswiderständen im Netzwerk sollte zu einem effizienten Transport von Elektronen in der Elektrode beitragen. Die Ergebnisse dieser Dissertation werden neue Wege zur Verbesserung der Energiedichte von Superkondensatoren sowie weiteren Anwendungen eröffnen.

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Dissertations / Theses on the topic 'High-density'

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