Дисертації: "Storage tanks Design and construction"

1

Marquez, Danilo Carleton University Dissertation Engineering Civil and Environmental. "Earthquake resistant design of liquid storage tanks." Ottawa, 1996.

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2

Timmins, David. "Observations on the design of rectangular storage tanks." Thesis, University of the West of Scotland, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296191.

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3

Ellis, David R. "The design of storm drainage storage tanks for self-cleansing operation." Thesis, University of Manchester, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306464.

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The use of storage tanks in sewerage systems has increased in recent years. The primary functions of such tanks are to attenuate flow and to retain pollutants within the sewer system. The main problem is to provide storage and effective separation of gross and suspended solids without incurring poor self - cleansing and associated high maintenance costs. The size of the required storage volume is dependant on the purpose for which the tank is to be used, but the end product of any design analysis is a fixed volume of storage. This project has involved the development of fullscale and laboratory computer controlled monitoring systems for the purpose of flow visualisation and digital imaging and for the comparative assessment of the sediment removal performance of different geometric configurations of overflow and storage tank. These systems used sophisticated control procedures and the latter had the facility to generate a flow hydrograph of any shape and duration and to superimpose on this hydrograph a pollutograph of synthetic cohesive sediment of any distribution. A wide variety of tanks have been constructed, mainly rectangular in plan shape (some circular), but both online and off-line and with and without an overflow structure. The use of benching to the chamber floor and the inclusion of a dry-weather flow channel were common but not universal features.

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4

Zmerli, Mustapha. "Optimization of the bottom plate of a ground-supported liquid storage tank." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-12052009-020116/.

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5

Abell, Dixon Harold. "A Study of the Cause of Failure of Rotationally Molded, High-Density Polyethylene, Sodium Hypochlorite Storage Tanks." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2609.

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The topic of chemical oxidative degradation in rotational molded polyethylene (high-density cross-linked) chemical (sodium hypochlorite) storage tanks is an industry problem that ranks at the top of current business issues for manufacturers of chemical storage tanks. The degradation of these tanks not only compromises the physical and mechanical properties of the tank material, but reduces the life expectancy of the tank, eventually resulting in catastrophic tank failure. Premature tank failure comes at a hefty cost. The reputation of the manufacturer is questioned often resulting in immediate loss of customer satisfaction and future business. The leaking of the chemical from the failed tank serves as a liable environmental hazard that jeopardizes the safety and welfare of its surroundings – people and environment. And the associated manufacturer of the failed tank is almost certainly responsible for the repair or replacement of the tank. All these associated problems and many more related to chemical tank failure cost this relatively small industry millions of dollars annually. The need to determine the failure mechanisms of these tanks is critically important. Such an understanding will provide industry with useful knowledge that will open the door for improvements in tank performance. There is no question that a deeper understanding of failure mechanisms will improve a tank manufacturer's reputation, increase business sales, and assure environmental safety. The addition of this knowledge will also instill consumer confidence in an industry that is considered to lack refined manufacturing processes and proven quality controls. Such advancements are keys to making rotational molding a cutting-edge, technology-driven process that prepares industry for future growth and development. The purpose of this research is to provide tested empirical data and proven expert analysis that can be utilized by companies in understanding the failure mechanisms of these tanks. The information regarding this topic was collected from various tank samples taken from Poly Processing, a leading manufacturer of rotationally molded polyethylene chemical storage tanks and producer of the examined samples, and Odyssey Manufacturing, a manufacturer of bulk sodium hypochlorite and the end user of the examined samples. In the final chapter of this research, a summary is presented of the important findings regarding the purpose of the thesis study.

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6

Fernandez-Munoz, Raul. "Design of solar power plant with coupled thermal storage." Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/16722.

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7

Meredith, James D. C. (James Douglas Charles). "Design, construction and testing of an ocean renewable energy storage scaled prototype." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/70437.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 95-96).
The concept for a new form of pumped storage hydro is being developed within the Precision Engineering Research Group at MIT: the Ocean Renewable Energy Storage (ORES) project. Large, hollow concrete spheres are created, fitted with a reversible pump-turbine and deployed to the sea floor. Water is then allowed to flow through the turbine, into the sphere, to produce power and power is stored back in the device by running the turbine backwards as a pump and evacuating the sphere. The first prototype of that concept is presented here. A land-based system was designed, built and tested to demonstrate its ability to store energy and test the viability of the manufacturing methods planned. The device was successfully built and cycled, storing 2Wh of energy. The round-trip efficiency of the device was severely affected by the low efficiency of the scaled down rotating equipment. It was also found that casting a monolithic sphere is preferable to assembling multiple pieces and that the interior of the sphere should be maintained at atmospheric pressure via a vent line.
by James D. C. Meredith.
S.M.

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8

Wang, Chin-Cheng E. "Design and analysis of the natural gas storage tank for automobiles." Ohio : Ohio University, 1998. http://www.ohiolink.edu/etd/view.cgi?ohiou1176236134.

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9

Chen, Shr-Hung. "Novel design and optimization of vehicle's natural gas fuel tank." Ohio : Ohio University, 1997. http://www.ohiolink.edu/etd/view.cgi?ohiou1177607369.

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10

Chan, Siu-wo, and 陳兆和. "Design, control and application of battery-ultracapacitor hybrid systems." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B38816660.

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11

Wallberg, Alexander. "Design and construction of a bidirectional DC/DC converter." Thesis, Uppsala universitet, Elektricitetslära, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-385240.

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A four quadrant general single-phase bi-directional DC/DC converter was designed and constructed for high effect systems. The target application for the DC/DC converter was to be used to transfer energy between different energy storages, a miniature DC power grid and the high voltage AC power city grid. The converter is capable of step-up and step-down operations in both directions i.e. it is bi-directional at varying voltage levels. Different DC/DC topologies were investigated, and thereafter simulations were performed in LTspice and Simulink to ensure its capabilities and functionalities. The result of the simulations was a two layered PI-regulator, controlling both the external DC-grid voltage and inductor current through the converter. Once a suitable topology and control strategy was found, a suitable power transistor investigated and a PCB driver card were developed with KiCad. The final converter is capable to seamlessly change between its four modes and controlling voltages up to 1200 V and currents up to 200 A.

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12

Argon, Cenk. "Turbo product codes for optical communications and data storage." Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/15350.

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13

Flaherty, Annette E. "Support of GRP vessels : a comparative study for the horizontal support of laminate construction GRP storage vessels." Thesis, University of Strathclyde, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366892.

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14

Loferski, Joseph R. "A reliability based design procedure for wood pallets." Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/52303.

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Pallets are widely used to efficiently store and handle goods and are often subjected to bending and impact loads. The consequences of structural failure of a loaded pallet can include loss of goods, increased labor and equipment costs, and possible severe or fatal injury to humans. - The pallet industry, which annually consumes nearly 20% of all lumber manufactured in the United States, recognized a need for a rational design methodology, based upon engineering principles, to ensure consistent safety and economy in pallets of any geometry. To satisfy this need a cooperative research project between Virginia Tech, the U. S. Forest Service, and the National Wooden Pallet and Container Association was established. The objective of the project was to develop methods to design pallets for strength, stiffness, and durability. A primary expected benefit of the design methodology is to allow comparison of different pallet designs on a performance basis, without the need for extensive physical testing. This dissertation presents the results of this cooperative research project. The developed methodology was computerized (Pallet Design System (PDS)) and is intended to allow pallet manufactures to obtain estimates of the maximum safe load capacity or the member dimensions required to resist known loads. Additionally, the program produces estimates of the durability and cost-per-use for pallets in specific service environments. PDS is limited in scope to pallets with up to four stringers and a maximum of 15 deckboards. Five different load types and four support modes can be analyzed. These include uniformly distributed and concentrated loads, and racked, stacked, and sling support modes. The techniques for estimating the strength and stiffness are based on matrix structural analysis and classical beam theory. The deckboard-stringer joints are modeled as spring elements, the stiffness of which are based upon characteristics of the fastener. Most fasteners commonly used in pallet construction (i.e. threaded nails or staples) can be analyzed. A probabilistic design technique based on mean value methods was applied in PDS to ensure safety in the resulting designs. The safety index was calibrated to pallet designs associated with warehouse load data. The physical properties of the material are estimated using either a modified clear-wood property approach (ASTM D-245 method), or in·graded testing of pallet lumber. The durability estimates are based upon studies of field data and economic analysis.
Ph. D.

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15

Begum, Latifa. "Natural and mixed convection in a horizontal cylindrical annulus with and without fins on inner cylinder." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=112556.

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Determination of the heat transfer coefficients for natural and mixed convection in horizontal annuli is important for designing double pipe heat exchangers and for energy storage systems. In part one and two of this study, the 2D numerical solution of the laminar natural convection of water in six internally finned horizontal annuli has been obtained. The fins are attached to the external surface of the inner cylinder. Only the symmetrical half of the horizontal annulus with three equally spaced longitudinal divergent solid and porous fins are considered. The parameters of the problem are Rayleigh number, fin height, permeability and porosity of the porous fin, etc. The above parameters are suitably varied to ascertain their effects on fluid flow and heat transfer. The results show that traditional solid fins provide much higher heat transfer rates compared to the porous fins. Part three of this work deals with mixed convective heat transfer (laminar natural and forced convections) of water in a vented annulus. The forced flow conditions are imposed by providing an inlet at the top and an outlet at the bottom. For various parameters of the problem, the average and local Nusselt numbers along the inner cylinder are calculated for water for both aiding and opposing flows. The fourth part of this study deals with numerical modeling of natural convection of nanofluids in a horizontal cylindrical annulus. Simulations are carried out for Cu-water nanofluids. The results, in general, show that nanoparticles systematically decrease the natural convective heat transfer coefficient on the inner cylinder. Practical and useful correlations are provided for calculating average heat transfer rates from the inner cylinder in the form of average equivalent thermal conductivity and average Nusselt number for all of the four cases discussed above. These correlations are new and will be helpful in designing heat exchangers.

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16

Helkin, Steven Alexander. "Design and optimization of a wave energy harvester utilizing a flywheel energy storage system." Master's thesis, University of Central Florida, 2011. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4774.

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This thesis details the design and optimization of a buoy used to collect renewable energy from ocean waves. The proposed buoy is a point absorber--a device that transforms the kinetic energy of the vertical motion of surface waves into electrical energy. The focus of the research is on the mechanical system used to collect the energy, and methods to improve it for eventual use in an actual wave energy harvester. A flywheel energy storage system was utilized in order to provide an improved power output from the system, even with the intermittent input of force exerted by ocean waves. A series of laboratory prototypes were developed to analyze parameters that are important to the success of the point absorb mechanical system. By introducing a velocity-based load control scheme in conjunction with flywheel energy storage, it was seen that the average power output by the prototype was increased. The generator load is controlled via a relay switch that removes electrical resistance from the generator--this sacrifices time during which power is drawn from the system, but also allows the buoy to move with less resistance. A simulation model was developed in order to analyze the theoretical wave absorber system and optimize the velocity threshold parameters used in the load control. Results indicate that the power output by the system can be substantially improved through the use of a flywheel energy storage control scheme that engages and disengages the electrical load based on the rotational velocity of the flywheel system. The results of the optimization are given for varying-sized generator systems input into the simulation in order to observe the associated trends.
ID: 030646228; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (M.S.M.E.)--University of Central Florida, 2011.; Includes bibliographical references (p. 111-114).
M.S.M.E.
Masters
Mechanical and Aerospace Engineering
Engineering and Computer Science
Mechanical Engineering; Computer Aided Mechanical Engineering Track

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17

Datta, Suparna. "New results on coding for M-ary runlength-limited channels." Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/33426.

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18

Dupéré, Richard. "Conception d'un dôme géodésique pour des réservoirs à lisier." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=55443.

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A roof over a manure reservoir eliminates the entry of precipitations, reduces odour and volatile gas emissions, lowers the storage and handling costs and alleviates environmental impacts.
Structural analysis and testing were carried out to establish the feasibility of geodesic domes as manure reservoir roofting. A stress analysis, conducted by computer was used to determine maximum compression loads on roof members. Compression tests were carried out in the laboratory to test two laminated designs and to evaluate the performance of a member joint.
Structural analysis showed that the Lamella type dome, with a diameter/height ratio of 4, offers the best geometry considering design criteria for manure roofs. Compression tests confirmed that laminated members, made of 38 x 89 mm and 38 x 140 mm pieces, can resist the design stress developed in a 22 meter diameter dome.
Loading tests revealed that non laminated wood members failed at 80% of the design load. However, the joints (formed by two 3,1 mm thick steel plates bolted to the members) were still able to resist an increase in loading.
Data obtained from the tests were used for a preliminary design of a geodesic roof taking into account specific conditions such as humidity and manure gas. However further study is required to adapt this concept to real conditions over a manure reservoir.
The cost of a 22 meter diameter dome, for covering manure reservoirs, is estimated at 79$/m$ sp2$ which is more expensive than the cost of the currently used, least expensive manure pit roof (wood truss design).

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19

Gurganus, Heath Alan. "Battery Energy Storage Systems to Mitigate the Variability of Photovoltaic Power Generation." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1495.

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Methods of generating renewable energy such as through solar photovoltaic (PV) cells and wind turbines offer great promise in terms of a reduced carbon footprint and overall impact on the environment. However, these methods also share the attribute of being highly stochastic, meaning they are variable in such a way that is difficult to forecast with sufficient accuracy. While solar power currently constitutes a small amount of generating potential in most regions, the cost of photovoltaics continues to decline and a trend has emerged to build larger PV plants than was once feasible. This has brought the matter of increased variability to the forefront of research in the industry. Energy storage has been proposed as a means of mitigating this increased variability -- and thus reducing the need to utilize traditional spinning reserves -- as well as offering auxiliary grid services such as peak-shifting and frequency control. This thesis addresses the feasibility of using electrochemical storage methods (i.e. batteries) to decrease the ramp rates of PV power plants. By building a simulation of a grid-connected PV array and a typical Battery Energy Storage System (BESS) in the NetLogo simulation environment, I have created a parameterized tool that can be tailored to describe almost any potential PV setup. This thesis describes the design and function of this model, and makes a case for the accuracy of its measurements by comparing its simulated output to that of well-documented real world sites. Finally, a set of recommendations for the design and operational parameters of such a system are then put forth based on the results of several experiments performed using this model.

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20

Anim-Appiah, Kofi Dankwa. "Interleaved concalenated coding for input-constrained channels." Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/15363.

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21

McGeever, Michael K. "Design of a very high speed dynamic RAM in gallium arsenide for an ATM switch /." Title page, contents and abstact only, 1995. http://web4.library.adelaide.edu.au/theses/09PH/09phm1449.pdf.

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22

Padigi, Sudhaprasanna Kumar. "Multivalent Rechargeable Batteries." PDXScholar, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2464.

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Li+ ion batteries have been the mainstay of high energy storage devices that have revolutionized the operating life time of consumer electronic devices for the past two decades. However, there is a steady increase in demand for energy storage devices with the ability to store more energy and deliver them at high power at low cost, without comprising safety and lifetime. Li-ion batteries have had significant challenges in increasing the amount of stored energy without affecting the overall lifetime and the ability to deliver stored energy. In order to store and deliver more energy, more lithium ions need to be inserted and extracted from a given electrode (cathode or anode). Upon inserting a large number of Li ions, the crystal lattice of the materials undergo severe mechanical distortions, leading to un-desirable structural changes. This results in underutilization of theoretical energy storage capacities of the electrodes and early failure of the batteries owing to instabilities in the electrode materials. Unlike monovalent Li+ ions, multivalent rechargeable batteries offer a potential solution to the above problems. Multivalent cations, such as Ca2+, are doubly-ionized as opposed to Li+ which is a monovalent cation. The advantages of using Ca2+ ions instead of Li+ ions are multifold. Due to the doubly-ionized nature, only half the number of Ca2+ ions need to be inserted and extracted from a given electrode to store and deliver energy from a high capacity cathode as compared to Li+ ions. This reduces the probability of lattice distortion and un-desirable structural changes, further leading to increased utilization of high theoretical energy storage capacities of the electrodes (cathode and anode). The use of Ca2+ ions also helps in delivering twice the amount of current density as compared to Li+ ions due to its doubly ionized nature. In this work, a set of eight metal hexacyanoferrate compounds were synthesized using the following metal ions: Ba2+, Mn2+, Zn2+, Co2+, Fe3+, Al3+, Sn4+, Mo5+. The resulting metal hexacyanoferrate compounds were subjected to physical characterization using scanning electron microscope (SEM) and powder x-ray diffraction (XRD), to determine physical properties such as size, morphology, unit cell symmetry and unit cell parameters. This was followed by electrochemical characterization utilizing cyclic voltammetry and galvanic cycling, to determine the specific capacity and kinetics involved in the transport of Ca2+ ions to store charge. Optical characterization of the metal hexacyanoferrates using Fourier transform infrared (FTIR) spectroscopy, allowed for the identification of metal-nitrogen stretching frequency, which was used as a measure of the strength of the metal-nitrogen bond to understand the role of the above mentioned metal ions in electron density distribution across the unit cell of the metal hexacyanoferrates. The specific capacity utilization of the metal hexacyanoferrates, when compared to the electronegativity values (Xi) of the above mentioned metal ions, the σ- parameter, and the metal-nitrogen stretching frequency (v), revealed an empirical trend suggesting that the materials (FeHCF, CaCoHCF and CaZnHCF) that possessed intermediates values for the above mentioned parameters demonstrated high capacity utilization (≥50%). Based on these empirical trends, it is hypothesized that a uniform distribution of electron density around a unit cell, as reflected by intermediate values of the electronegativity (Xi) of the above mentioned metal ions, the σ-parameter and the metal-nitrogen stretching frequency (v), results in minimal electrostatic interactions between the intercalating cation and the host unit cell lattice. This results in relatively easy diffusion of the cations, leading to high specific capacity utilization for metal hexacyanoferrate cathodes. These parameters may be used to select high efficiency cathode materials for multivalent batteries.

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23

Nováček, Filip. "Návrh uskladňovací nádrže." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230600.

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The aim of this diploma thesis is to design of storage tank for petroleum. The thesis is divided into two parts. In the first part of the work is focused on introducing the known types of storage tanks, their parts, use and benefits. The thesis also briefly summarized legislation regarding this issue. The second part is the actual design of storage tank. It was the strength calculation tanks according to EN 14 015. It was also a voltage FEM analysis of shell and tank roof. Result of work is a design drawing of the storage tank.

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24

Gerth, Robert. "The Role of Production Topology in Information Based Structuring of Organizations : The design of craft-based and industrialized construction firms." Doctoral thesis, KTH, Produktionssystem, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-133918.

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Industrialization of construction is a business strategy to significantly improve competitiveness. However, the organization structure of the construction firms needs to support the new production system. The knowledge on why and how this business development can be accomplished is scarce, both within academia and in business practice. This research seeks to fill this knowledge gap. The purpose of organization structure and the production system have is to coordinate the firm’s processes and control the work performing resources. Information is one of the most fundamental dimensions for steering and controlling the work. The different information types are determined by the firm’s product customization strategy and the production system flexibility. Further, diverse information types are managed in different extent by the organizational steering mechanisms. Consequently, firms with dissimilar customization strategy or production flexibility should organizationally be designed differently in order to be efficient. The developed model identifies four generic production topologies: “engineer-to-order” (ETO), “manufacture-to-order” (MTO), “assembly-to-order” (ATO), and “make-standard-products” (MSP). The differences between the topologies can be related to the location of the “customer-order-decoupling-point” (CODP) in the product realization process; and to what extent the upstream and downstream processes continuously use stored information or process information to accomplish the work of each product order. The model predicts which organization structure mechanisms that should be used for which processes for each production topology. It is the specific configuration of the mechanisms that gives each production topology their organizational capability. The model has been validated by case studies in four organizations, each representing one of the four generic production topologies. Three cases considered housing and one studied truck manufacturing. It has been shown that the conventional housing firms have an ETO-production topology, while industrialized housing firms belonging to one of the others, i.e. MTO, ATO or MSP. The reason is that ETO-firms rely on crafts-based production to manage the work, while the other topologies base their steering mechanisms on industrial principles. These two types of production are fundamentally different, which also explain the need for different organization structures. The research complements previous knowledge and significantly increases the ability to predict, analyze and explain an organization’s design and behavior. The model can be used in practice to guide business development work and performance improvement programs.

Research funder: SBUF (The development fund of the Swedish construction industry). QC 20131113

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25

Jensen, Deron Eugene. "System-wide Performance Analysis for Virtualization." PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/1789.

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With the current trend in cloud computing and virtualization, more organizations are moving their systems from a physical host to a virtual server. Although this can significantly reduce hardware, power, and administration costs, it can increase the cost of analyzing performance problems. With virtualization, there is an initial performance overhead, and as more virtual machines are added to a physical host the interference increases between various guest machines. When this interference occurs, a virtualized guest application may not perform as expected. There is little or no information to the virtual OS about the interference, and the current performance tools in the guest are unable to show this interference. We examine the interference that has been shown in previous research, and relate that to existing tools and research in root cause analysis. We show that in virtualization there are additional layers which need to be analyzed, and design a framework to determine if degradation is occurring from an external virtualization layer. Additionally, we build a virtualization test suite with Xen and PostgreSQL and run multiple tests to create I/O interference. We show that our method can distinguish between a problem caused by interference from external systems and a problem from within the virtual guest.

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26

Sinha, Arpita. "Evolving Nano-scale Associative Memories with Memristors." PDXScholar, 2011. https://pdxscholar.library.pdx.edu/open_access_etds/445.

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Associative Memories (AMs) are essential building blocks for brain-like intelligent computing with applications in artificial vision, speech recognition, artificial intelligence, and robotics. Computations for such applications typically rely on spatial and temporal associations in the input patterns and need to be robust against noise and incomplete patterns. The conventional method for implementing AMs is through Artificial Neural Networks (ANNs). Improving the density of ANN based on conventional circuit elements poses a challenge as devices reach their physical scalability limits. Furthermore, stored information in AMs is vulnerable to destructive input signals. Novel nano-scale components, such as memristors, represent one solution to the density problem. Memristors are non-linear time-dependent circuit elements with an inherently small form factor. However, novel neuromorphic circuits typically use memristors to replace synapses in conventional ANN circuits. This sub-optimal use is primarily because there is no established design methodology to exploit the memristor's non-linear properties in a more encompassing way. The objective of this thesis is to explore denser and more robust AM designs using memristor networks. We hypothesize that such network AMs will be more area-efficient than the traditional ANN designs if we can use the memristor's non-linear property for spatial and time-dependent temporal association. We have built a comprehensive simulation framework that employs Genetic Programming (GP) to evolve AM circuits with memristors. The framework is based on the ParadisEO metaheuristics API and uses ngspice for the circuit evaluation. Our results show that we can evolve efficient memristor-based networks that have the potential to replace conventional ANNs used for AMs. We obtained AMs that a) can learn spatial and temporal correlation in the input patterns; b) optimize the trade-off between the size and the accuracy of the circuits; and c) are robust against destructive noise in the inputs. This robustness was achieved at the expense of additional components in the network. We have shown that automated circuit discovery is a promising tool for memristor-based circuits. Future work will focus on evolving circuits that can be used as a building block for more complicated intelligent computing architectures.

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27

Thomas, Noura. "Analysis of right-turn lane length in left-hand traffic countries at signalised intersections of urban roads." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2016. https://ro.ecu.edu.au/theses/1781.

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Analysis of the right turn lane length of urban roads in left-hand traffic countries, such as Australia, UK and India (left-turn lane length in right-hand traffic countries such as USA), at signalised intersections encounters two main geometric features namely, deceleration length and storage length. The literature shows that in routine practice, the deceleration length is generally estimated by using constant deceleration rate. Many researchers consider this assumption for all design speeds unrealistic as it does not reflect the influence of the pavement condition. Hence, it may be desirable to consider the pavement’s condition in terms of its longitudinal coefficient of friction in the design analysis. In regard to the storage length, a large number of the current guidelines and models estimate the storage length of right-turn lane at signalised intersections under split phase. Hence, there is a need to examine other phase types and timings and integrate the signal timing as a part of the geometric design In this thesis, two analytical expressions have been analysed for the design of deceleration length. The first expression assumes a constant deceleration rate, and the second expression employs the concept of forces on a rotating wheel in which the coefficient of longitudinal friction between a vehicle’s tyres and the road surface is considered. The calculated deceleration lengths by these two expressions were compared with the recommended values in American and Australian standards as well as with the deceleration lengths that were obtained by a recent simulation study presented in the literature. It has been found that applying a constant deceleration rate of 2.74 m/s2 in the first expression provides the values of deceleration length comparable to most guidelines and studies. The second expression highlights the importance of using the pavement design in terms of the coefficient of friction to reduce the deceleration length in the case of limited space. A MATLAB based simulation programme has been developed to provide an estimate of the right-turn lane storage length for different traffic volumes in order to avoid the problems associated with blocking and overflow of right turn vehicles in 95% of cycles. In established intersections that cannot be modified due to physical constraints, the model is flexible enough to examine different signal phase types and timings and provides other solutions to reduce overflow and/or blockage situations. The simulation model also takes into consideration the leftover queue. The model results have been compared against an available analytical method in which similar signal phases and timings were investigated. The outcomes are similar to those of the analytical model in most of the signal phase types. The simulation model provides the flexibility to estimate the right-turn lane length for different combinations of through lane and right-turn lane traffic volumes. The developed simulation model has also been validated against the field data using three parameters, namely 95th percentile of maximum queue, overflow cycle percentage, and blockage cycle percentage. Comparing with the field observations yields a level of accuracy in the range of 78%-85%. Finally this simulation model has been used to optimise the green time in the case of split phase that demonstrates a large difference in traffic volumes of two opposite approaches; this could reduce the mean wait time by up to 28%.

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Yeo, Yong-Kee. "Dynamically Reconfigurable Optical Buffer and Multicast-Enabled Switch Fabric for Optical Packet Switching." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/14615.

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Optical packet switching (OPS) is one of the more promising solutions for meeting the diverse needs of broadband networking applications of the future. By virtue of its small data traffic granularity as well as its nanoseconds switching speed, OPS can be used to provide connection-oriented or connectionless services for different groups of users with very different networking requirements. The optical buffer and the switch fabric are two of the most important components in an OPS router. In this research, novel designs for the optical buffer and switch fabric are proposed and experimentally demonstrated. In particular, an optical buffer that is based on a folded-path delay-line tree architecture will be discussed. This buffer is the most compact non-recirculating optical delay line buffer to date, and it uses an array of high-speed ON-OFF optical reflectors to dynamically reconfigure its delay within several nanoseconds. A major part of this research is devoted to the design and performance optimization of these high-speed reflectors. Simulations and measurements are used to compare different reflector designs as well as to determine their optimal operating conditions. Another important component in the OPS router is the switch fabric, and it is used to perform space switching for the optical packets. Optical switch fabrics are used to overcome the limitations imposed by conventional electronic switch fabrics: high power consumption and dependency on the modulation format and bit-rate of the signals. Currently, only those fabrics that are based on the broadcast-and-select architecture can provide truly non-blocking multicast services to all input ports. However, a major drawback of these fabrics is that they are implemented using a large number of optical gates based on semiconductor optical amplifiers (SOA). This results in large component count and high energy consumption. In this research, a new multicast-capable switch fabric which does not require any SOA gates is proposed. This fabric relies on a passive all-optical gate that is based on the Four-wave mixing (FWM) wavelength conversion process in a highly-nonlinear fiber. By using this new switch architecture, a significant reduction in component count can be expected.

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Labidi, Mouchira. "Optimisation de chaufferies collectives multi-energies : dimensionnement et commande de systèmes de stockage thermique par hydro-accumulation." Thesis, Perpignan, 2015. http://www.theses.fr/2015PERP0007.

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Les travaux présentés dans ce manuscrit portent sur l’optimisation d’une chaufferie collective multi-énergie en l’équipant d’un système de stockage thermique de type hydro-accumulation. L’efficacité de ce dernier dépend de sa capacité à conserver son énergie initiale. Ainsi, pour minimiser les pertes thermiques, le système de stockage doit être correctement isolé. Un modèle de ballon d’hydro-accumulation stratifié est développé et validé expérimentalement. Une étude paramétrique est menée afin d’étudier l’impact, sur les pertes thermiques, de paramètres géométriques et météorologiques. Ensuite, une approche de dimensionnement, fondée sur une stratégie de gestion séquentielle et une étude paramétrique est proposée. Plusieurs critères énergétiques et économiques peuvent ainsi être évalués pour différents volumes de stockage thermique. L’approche de dimensionnement proposée a été appliquée à plusieurs sites exploités par Cofely GDF-Suez, notre partenaire industriel. Les résultats obtenus montrent que le dimensionnement optimal du système de stockage et la gestion intelligente du procédé permettent d'optimiser le fonctionnement d’un site. Des économies énergétiques et financières importantes peuvent ainsi être réalisées. La stratégie de gestion séquentielle proposée n’anticipe pas les besoins du réseau de chaleur. C’est pourquoi une stratégie fondée sur la commande prédictive (MPC pour Model Predictive Control) est susceptible d’améliorer le fonctionnement et les performances d’une chaufferie collective équipée d’un système d’hydro-accumulation. Afin de mettre en œuvre un tel contrôleur, la puissance thermique demandée par le réseau de chaleur doit être correctement prédite. Par conséquent, une méthode de prédiction a été développée. Elle s’appuie sur une analyse multi-résolution par transformée en ondelettes discrète et sur l’utilisation de réseaux de neurones artificiels de type perceptron multicouche. La stratégie séquentielle (non prédictive) et la stratégie prédictive ont été appliquées à une chaufferie collective mixte située dans une commune du nord de la France. Pour ce cas d’étude, la stratégie prédictive est plus efficace. De plus, les résultats montrent que, quelle que soit la stratégie utilisée, équiper la chaufferie d’un système d’hydro-accumulation correctement dimensionné est un investissement rentable. Il permet de minimiser la consommation d’énergie fossile et, par conséquent, le coût économique et les émissions de CO2
The present work deals with optimizing a multi-energy district boiler by adding to the plant a thermal water storage tank. The effectiveness of such a system depends on how long the stored energy can be kept without considerable degradation. The storage tank should be properly insulated to reduce the rate of heat loss. Thus, firstly, a stratified water thermal storage model is developed and experimentally validated. A parametric study is carried out to determine the influence of geometric and meteorological parameters on heat loss. Next, a reliable sizing method based on a sequential management strategy and a parametric study is proposed. Various energy and economic criteria have been evaluated for a range of thermal storage sizes. The proposed methodology has been applied to many plants managed by Cofely GDF-Suez, our industrial partner. Results highlight the ability of a thermal storage tank (optimally sized and managed) to improve the operation of a multi-energy district boiler and realize significant energy and economic savings. The main drawback of the proposed sequential management strategy lies in not taking into account the future power demand. That is why a strategy based on a Model Predictive Controller (MPC) is likely to improve operation and performance. In order to implement such a controller, the power demand has to be accurately forecasted. As a consequence, a short-term forecast method, based on wavelet-based Multi-Resolution Analysis (MRA) and multilayer Artiﬁcial Neural Networks (ANN) is proposed. Both the sequential and the predictive strategies are applied to a northeast France multi-energy district boiler selected as a case study. The main result to retain is that the efficiency of water thermal storage tank is mainly related to its design and the way it is managed. For this case study, the predictive strategy regardless the size of the storage tank, the predictive strategy is more reliable. Furthermore, in all cases an adequately sized and managed thermal storage tank is a profitable investment. It allows the fossil energy consumption to be signiﬁcantly reduced. The same remark applies to the functioning costs and CO2 emissions

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Arzamendia, Lopez Juan Pablo. "Métholodogie de conception des matériaux architecturés pour le stockage latent dans le domaine du bâtiment." Thesis, Lyon, INSA, 2013. http://www.theses.fr/2013ISAL0060/document.

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L'utilisation de systèmes de stockage par chaleur latente constitue une solution permettant l'effacement du chauffage d'un bâtiment résidentiel pendant les périodes de forte demande. Une telle stratégie peut avoir pour objectif le lissage des pics d'appel en puissance du réseau électrique. Cependant, la faible conductivité des matériaux à changement de phase (MCP) qui constituent ces systèmes et le besoin d'une puissance de décharge importante imposent l'utilisation de matériaux dits "architecturés" afin d'optimiser la conductivité équivalente des matériaux stockeurs. Nos travaux s'intéressent plus particulièrement à la méthodologie pour la conception de matériaux pour ces systèmes afin de satisfaire aux exigences de stockage d'énergie et de puissance de restitution. La méthodologie proposée dans ces travaux de thèse est dénommé « Top-down methodology ». Cette méthodologie comporte trois échelles : l'échelle bâtiment (top), l'échelle système et l'échelle matériau (down). L'échelle bâtiment a comme objectif de spécifier le cahier des charges. A l'échelle système, des indicateurs de performance sont définis. Enfin, à l'échelle matériau, l'architecture du matériau solution est proposée. Un outil numérique modélisant le système de stockage par chaleur latente de type échangeur de chaleur air/MCP à été développé pour évaluer les indicateurs de performance. Ce modèle numérique est vérifié avec un cas analytique et validé par comparaison avec des données expérimentales. La méthodologie développée est mise en œuvre dans un deuxième cas d'étude pour le même type de système de stockage. L'analyse du système via les nombres adimensionnels permet d'obtenir des indicateurs de performance du système. A l'issue de cette étape, les propriétés matériaux et fonctionnelles optimales du système sont donc connues. Enfin, un matériau architecturé est alors proposé afin de satisfaire les exigences du système de stockage. Nous montrons alors que par l'intermédiaire d'une plaque sandwich contenant des clous et du MCP les propriétés matériaux nécessaires sont obtenues. De plus, afin de satisfaire aux exigences en termes de propriétés fonctionnelles, le design du système est modifié en ajoutant des ailettes sur les surfaces d'échange. Nous montrons que avec 20 ailettes de 3mm d'épaisseur sur la surface d'échange de la planche à clous, le chauffage est effacé pendant 2h lors de la période de forte demande journalière pendant l'hiver
The use of energy storage systems that exploit latent heat represents a promising solution to erase the heating demand of residential buildings during periods of peak demand. Equipping a building with such components can contribute to the goal of peak shaving in terms of public electricity grid supply. Significant drawbacks, however, are the low thermal conductivity of Phase Change Materials (PCM) that typically constitute such systems,and the requirement for a high rate of discharge. Consequently, the use of so-called architectured materials has been put forward as a means to optimize the effective conductivity of storage materials. Our work is focused upon the development of a methodology to design optimal materials for such systems that meet the criteria of energy storage and energy output. A so-called “top-down metholodogy” was implemented for the present work. This approach includes three scales of interest: building (top), system and material (down). The aim of the building scale analysis is to formulate a set of general design requirements. These are complemented by performance indicators, which are defined at the scale of the system. Finally, at the scale of the material, the architecture of the identified material is elaborated. A numerical simulation tool was developed to determine performance indicators for a latent heat energy storage system comprising of an air/PCM heat exchanger. This model was tested against a benchmark analytical solution and validated though comparison to experimental data. The developed methodology is applied to the specific case of an air/PCM exchanger latent-heat energy storage system. The system is analysed through the study of dimensionless numbers, which provide a set of design indicators for the system. As a result of this stage, the optimal material and functional properties are thus identified. Finally, an architectured material is proposed that would satisfy the design requirements of the storage system. We demonstrate that an arrangement composed of a sandwich of planar layers with nails and PCM can offer the required material properties. Furthermore, in order to meet the desired functional properties, the system design is modified by the addition of fins at the exchange surfaces. With the addition of 20 fins of 3mm thickness attached to the exchange surface of the sandwich panel, the storage system eliminated the heating demand for 2 hours during the period of high daily demand in winter

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Monfors, Lisa, and Corinne Morell. "Byggnadsutformning för ett framtida varmare klimat : Klimatscenariers påverkan på energianvändning och termisk komfort i ett flerbostadshus och alternativa byggnadsutformningar för att förbättra resultatet." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-79953.

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När byggnader projekteras används klimatfiler från 1981-2010 för att dimensionera konstruktionen och energisystemet. Detta leder till att byggnader dimensioneras för ett klimat som varit och inte ett framtida klimat. SMHI har tagit fram olika klimatscenarier för framtiden som beskriver möjliga utvecklingar klimatet kan ta beroende på fortsatt utsläpp av växthusgaser. Dessa scenarier kallas för RCP (Representative Concentration Pathways). I denna studie används två olika klimatscenarier, RCP4,5 och RCP8,5. Siffran i namnet står för den strålningsdriving som förväntas uppnås år 2100. I RCP4,5 kommer medelårstemperaturen öka med 3 °C fram till år 2100 jämfört med referensperioden 1961-1990. För samma tidsperiod sker en ökning på 5 °C enligt RCP8,5. Ett flerbostadshus certifierad enligt Miljöbyggnad 2.2 nivå silver placerat i Vallentuna i Stockholms län används i denna studie som referensbyggnad. Byggnaden simuleras i programmet IDA ICE där den utsätts för RCP4,5 och RCP8,5. Resultatet visar att byggnaden inte skulle klara av kraven för Miljöbyggnad 2.2 gällande termiskt klimat sommar i något av de två klimatscenarierna. De operativa temperaturerna blir för höga i byggnaden utan att tillsätta komfortkyla. Byggnaden ändras för att se vilka faktorer som kan förbättra resultatet gällande det termiska klimatet. Resultatet visar att värmelagringsförmåga hos byggmaterial och solavskärmning har störst påverkan på det termiska klimatet. I studien gjordes flertal olika kombinationer av byggnadsutformningar. Enbart kombinationen av en tung stomme av betong tillsammans med fönster med lägre g-värde klarar kraven för Miljöbyggnad 2.2 i RCP4,5 och RCP8,5 utan komfortkyla. Kombinationen får lägst energianvändning i RCP8,5 av de olika kombinationerna som testats i studien. En kombination av tung stomme av KL-trä med lågt U-värde, fönster med lägre g-värde och komfortkyla får lägst energianvändning i grundklimatet och RCP4,5 av de olika kombinationerna som testats i studien trots användningen av komfortkyla. Frågan om vilket alternativ som är bäst ur ett hållbarhetsperspektiv är svårt att svara på. Det finns många aspekter som behöver tas i hänsyn till som byggnadens totala klimatavtryck både i tillverkning och användning. Oavsett val av konstruktion är det viktigt att projektera för att komfortkyla och solavskärmning skall kunna appliceras när ett varmare klimat råder.
When buildings are designed climate files from 1981 to 2010 are used to construct the building and its energy system. This leads to building being designed to a climate that has been and not to a future warmer climate that will come. SMHI has developed different climate scenarios for the future that describe different paths the climate can take depending on continued emissions of greenhouse gas. This climate scenarios are called RCP (Representative Concentration Pathways) In this study two of the climate scenarios, RCP4,5 and RCP8,5 are used. The number in the name stands for the radiation forcing that is expected in the year 2100. In RCP4,5 the mean average air temperature will increase with 3 °C until year 2100 compared to the reference period 1961-1990. In the same time period RCP8,5 will increase with 5 °C. An apartment building certified according to Miljöbyggnad 2.2 level silver placed in Vallentuna, Stockholms län is used as a reference building. The building is simulated through the simulation software program IDA ICE where it´s exposed to RCP4,5 and RCP8,5. The results demonstrate that the reference building would not meet Miljöbyggnad 2.2 requirement in the indicator about thermal comfort during summer. The operative temperature in the building is too high unless comfort cooling is used. The design of the building changes to see what factors can improve the results regarding the thermal comfort. The results demonstrate that thermal conductivity and solar shading has the greatest impact on thermal comfort. In this study several combinations of different building designs were made. Only the combination of a concrete frame with windows with low g-value met the requirement of Miljöbyggnad 2.2 regarding the thermal comfort during summer without using comfort cooling in RCP4,5 and RCP8,5. The combination had the lowest energy demand in RCP8,5 of all the combinations tested in the study. A combination of cross laminated wood frame with low U-value, windows with low g-value and comfort cooling had the lowest energy demand in the original climate file and RCP4,5 despite the use of comfort cooling. The questing about which building construction is the best from a sustainable perspective is difficult to answer. To answer that question the building´s total climate footprint in both production and use must be calculated. Regardless of the choice of building construction it is important to have in mind when designing a building that comfort cooling and solar shading should be easily applied when a warmer climate will prevail.

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Krmaš, Jan. "Hospic sv. Michaela." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226675.

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The topic of the master thesis is new medico-social facility hospice St. Michaela. The purpose of the object is the maximizing of improvement in the quality of life of dying, severely ill and incurable patients, with the use of palliative care. The construction follows the Complex of Regional Hospital Náchod. Together with as a retirement home Náchod completes a support network of health and social care. The building is designed as a four-building storey and is partially embedded into the sloping terrain. Floors are divided into individual facilities and together constitute a functional unit. In the basement is the technical room, warehouses, garages and kitchen facilities. On the ground floor are then socio-public rooms and facilities. On the second floor is located hedmaster of hospice and accommodation area. The third floor is devoted to the accommodation area. The proposed structure made of brick longitudinal system, supplemented by concrete basement walls. The horizontal structure is made of filigree ceiling panels. Stairs are designed as a precast concrete and steel. Individual roof structures is made from unwalkable, walkable and vegetation compositions. The cladding consists of ventilated facade of glass and wooden panels. Foundations are designed from the lineal foundation.

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(8455983), Harsh Bohra. "STUDIES ON ABOVEGROUND STORAGE TANKS SUBJECTED TO SEISMIC EXCITATION AND FOUNDATION SETTLEMENT." Thesis, 2020.

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The author aims to investigate the current design provision for seismic and foundation settlement design of aboveground open-top storage tanks using finite element analysis. The thesis is divided into two independent but closely related studies: (1) seismic analysis of open-top storage tanks with flexible foundation and (2) fitness-for-service of open-top storage tanks subjected to differential settlement.

The present seismic design provisions in American Petroleum Institute’s storage tank standard API 650 (2013) assumes the tank foundation is rigid and therefore, ignores the effect of uplift during a seismic excitation. In the first study, the objective was to quantitatively critique rigid foundation assumption and conclude if the assumption is acceptable or not for a given tank geometry. Tanks with three different height to diameter ratio (H/D), i.e aspect ratios, of 0.67, 1.0 and 3.0 representing broad, nominal and slender geometry, respectively, were modelled having both rigid and flexible foundations. The flexible foundation was modelled with series of non-linear compression only springs. Additionally, for each tank model two different hydrodynamic pressure distribution suggested by (1) Housner and (2) Jacobsen-Veletsos were applied which are used by API 650 and Eurocode 8, respectively. Geometric non-linear analysis with non-linear material properties was conducted (GMNA) using Riks algorithm in Abaqus finite element analysis (FEA) program. The hoop stresses, longitudinal stresses, uplift and buckling capacity of each rigid foundation tank model were compared with its respective flexible foundation tank model and corresponding API 650 rule based provisions. It was observed that the assumption of rigid foundation from design point of view is acceptable for the broad tank, however, for the nominal and slender tanks this assumption is not acceptable. The buckling capacity of nominal and slender tanks having flexible foundation are significantly lower compared to rigid foundation. Therefore, the effect of uplift should not be neglected for design purposes for nominal and slender tank geometries.

In the second study, an alternative method for evaluating the structural integrity of storage tank subjected to differential settlement is proposed. The limitations of the existing method in API 653 (2014), currently used in the industry are highlighted. The tank settlement is measured underneath

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the tank bottom along the tank circumference at discrete locations. The settlement can be transformed into a Fourier series by combining different harmonic components. In the existing API 653 method there is no distinction between the effects of different harmonic components whereas in the proposed method the effects of first five harmonic components are individually accounted and the cumulative damage is evaluated. The proposed method is formulated based on FEA conducted on twenty-one different tank models with each having different tank geometry. The limiting settlement value for each harmonic wave number is found for a given tank geometry by conducting GMNA using Riks algorithm, and a generalized trend is found for each harmonic wave number. The proposed method is further validated by performing numerous FEA simulations. The simulations were conducted for several tank models subjected to four representative actual measured settlement data. A set of tank models used in the validation was generated using random tank geometries and design parameters to have a blind test of the proposed method. Finally, a comparison is made between allowable settlement based on the API 653 method, the proposed method and the FEA. It was observed that the proposed method consistently results in conservative results compared to FEA. In contrast the API 653 method does not always result in conservative results. For some measured settlement data, the API 653 method gives overly conservative values and for others it gives non-conservative values. Moreover, the API 653 method is based on the beam theory which may not capture the true shell behavior. Therefore, the API 653 method requires modifications. The proposed method on the other hand is consistent and is based FEA which can capture the true shell behavior as it is formulated using shell theory. Therefore, it is recommended that the existing method in API 653 shall be replaced with the proposed method to determine the fitness of tank under differential settlement.

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Hu, Jing. "Evaluation of parameters influencing oxygen transfer efficiency in a membrane bioreactor." Thesis, 2006. http://hdl.handle.net/10125/20477.

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35

"Coding for storage systems." 2014. http://repository.lib.cuhk.edu.hk/en/item/cuhk-1291569.

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Анотація:

Chen, Junyu.
Thesis M.Phil. Chinese University of Hong Kong 2014.
Includes bibliographical references (leaves 56-61).
Abstracts also in Chinese.
Title from PDF title page (viewed on 25, October, 2016).

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Huang, Cheng-Yi, and 黃承一. "Using Visual-Based User Interface Construction Methodology for the Man Machine Interface Design and Implementation of Storage Systems." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/45657166539502005603.

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碩士
國立交通大學
資訊學院碩士在職專班資訊組
95
When the requirements of Man Machine Interface (MMI) are changed, programmers must change the related programs of MMI if they use the conventional MMI development. Therefore, they have to take long time to develop and spend much effort to maintain programs of MMI. The Software Engineering Laboratory of NCTU had developed Visual-Based User Interface Construction Methodology. This methodology can improve the productivity, quality, and maintainability of MMI software. In this thesis, we use this methodology for the MMI design and implementation of storage systems, and try to conquer UI problems using conventional MMI development. For the typical and various Man Machine Interfaces of storage systems, we design the Visual MMI Development for Storage Systems. It includes Visual Authoring Process and Generic MMI Engine for storage systems. In order to demonstrate the feasibility of the Visual MMI Development for Storage Systems, we implement a software framework with Generic MMI Engine that can manipulate the output data of Visual Authoring Tool, interact with the Management API of storage systems, and use this system to control a functional storage adapter. A real application example using the proposed approach is applied to demonstrate the applicability of the methodology.

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Schmidt, Dennis Patrick. "Design and testing of a modular hydride hydrogen storage system for mobile vehicles." 1985. http://hdl.handle.net/2097/27531.

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"Intelligent battery management system for electric vehicles." Thesis, 2010. http://library.cuhk.edu.hk/record=b6075241.

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A vehicular battery must consist of a large number of cells to provide the necessary energy and power. Management only at the level of the battery pack causes out-of-investigation cells and lack of cell equalization ability. Therefore, in the smart module concept, cells are first grouped into modules, which are then connected to the battery pack. Each module is an independent unit with a controller to investigate and control cells. Based on this concept, the work in this thesis redistributes tasks among module controllers and a central controller, applies a self-power design to enhance module independence, and selects the newly developed automotive ICs and sensors. Finally, a prototype of the BMS has been developed and successfully applied in a series of HEVs.
Cell equalization is a crucial technique to balance the cells inside a battery pack, with the ability to maximize pack capacity and protect cells from damage. For the bi-directional Cuk equalizing circuit, we propose a SoC based, instead of voltage based, fuzzy controller to intelligently determine the equalizing current, with the aim of reducing equalizing duration, enhancing equalizing efficiency, and protecting cells. The inputs to the controller are specially designed as the difference in SoC, the average SoC, and the total internal resistance. Because of the lack of theoretical analysis on equalizing current in the electrochemistry field, we utilize a fuzzy controller to incorporate the experience and knowledge of experts. Simulations and experiments verify its availability and efficacy. Especially for a LiFePO4 battery, a large SoC difference may lead to only a small difference in voltage and cause the failure of a traditional voltage based equalizer. The SoC based method successfully avoids this problem and obtains good performance in equalizing LiFePO4 cells.
Fast charge is intended to charge a battery as fast as possible, without any damage and with high energy efficiency, thus helping to reduce vehicle out-of-service time and promote the commercialization of EVs. Battery safety and charging efficiency are partially reflected by the increase in temperature during the charging process. Therefore, the aims of this thesis were to accelerate charging speed and reduce the temperature increase. We introduce a model predictive control framework to control the charging process. An RC model and the modified enhanced self-correcting model are employed to predict the future SoC in simulations and experiments respectively. A single-node lumped-parameter thermal model and a neural network trained by real experimental data are also applied respectively. In addition, a genetic algorithm is applied to optimize the charging current under multiple objectives and constraints. Simulation and experimental results strongly demonstrate that the Pareto front of the proposed algorithm dominates that of the popular constant current constant voltage charge method.
State of charge (SoC) is a battery state indicating its residual capacity. It is the fundamental state of the battery and is the basis for other battery operations. However, SoC is not a directly measurable state and has to be obtained by estimation techniques. Aiming to enhance the anti-noise ability of SoC estimation in a real vehicle environment, we propose a SoC estimation framework consisting of an adaptive nonlinear diffusion filter to reduce the noise of current measurement, a self-learning mechanism to remove its zero-drift, an open loop coulomb counting estimator and a model based closed loop filter to estimate SoC, and a data fusion unit to reach the final estimation result. In a simulation study, the closed loop filter is implemented based on an RC model and Hinfinity filter. In experiments and application, we modify the enhanced self-correcting model to model a type of LiFePO4 battery and apply an extended Kalman filter to estimate SoC. The framework has been demonstrated to improve accuracy and anti-noise ability, and achieves the technique upgrading goal recently published by the Chinese government.
The automotive industry has experienced a significant boom in recent years, accelerating the problems of energy shortage and environmental disruption around the world. To solve the two problems, electric vehicles (EVs), including battery electric vehicles (BEV), hybrid electric vehicles (HEV), and fuel-cell electric vehicles (FEV), have been proposed and studied in recent years. Despite the efforts devoted to the development of EVs by both the scientific research and industrial communities, there are still many obstacles hindering the mass commercialization of EVs. Among these obstacles, the battery system, the new energy storage component in EVs, is one of the most important yet most difficult parts of EV design, and the battery management system (BMS) is recognized as the single most important technical issue in the successful commercialization of EVs.
Yan Jingyu.
Adviser: Xu Yangsheng.
Source: Dissertation Abstracts International, Volume: 73-03, Section: B, page: .
Thesis (Ph.D.)--Chinese University of Hong Kong, 2010.
Includes bibliographical references (leaves 166-182).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstract also in Chinese.

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39

Davis, Jonathan Tesner. "Membraneless Electrolyzers for Solar Fuels Production." Thesis, 2019. https://doi.org/10.7916/d8-ypyq-6d71.

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Solar energy has the potential to meet all of society’s energy demands, but challenges remain in storing it for times when the sun is not shining. Electrolysis is a promising means of energy storage which applies solar-derived electricity to drive the production of chemical fuels. These so-called solar fuels, such as hydrogen gas produced from water electrolysis, can be fed back to the grid for electricity generation or used directly as a fuel in the transportation sector. Solar fuels can be generated by coupling a photovoltaic (PV) cell to an electrolyzer, or by directly converting light to chemical energy using a photoelectrochemical cell (PEC). Presently, both PV-electrolyzers and PECs have prohibitively high capital costs which prevent them from generating hydrogen at competitive prices. This dissertation explores the design of membraneless electrolyzers and PECs in order to simplify their design and decrease their overall capital costs. A membraneless water electrolyzer can operate with as few as three components: A cathode for the hydrogen evolution reaction, an anode for the oxygen evolution reaction, and a chassis for managing the flows of a liquid electrolyte and the product gas streams. Absent from this device is an ionically conducting membrane, a key component in a conventional polymer electrolyte membrane (PEM) electrolyzer that typically serves as a physical barrier for separating product gases generated at the anode and cathode. These membranes can allow for compact and efficient electrolyzer designs, but are prone to degradation and failure if exposed to impurities in the electrolyte. A membraneless electrolyzer has the opportunity to reduce capital costs and operate in non-pristine environments, but little is known about the performance limitations and design rules that govern operation of membraneless electrolyzers. These design rules require a thorough understanding of the thermodynamics, kinetics, and transport processes in electrochemical systems. In Chapter 2, these concepts are reviewed and a framework is provided to guide the continuum scale modeling of the performance of membraneless electrochemical cells. Afterwards, three different studies are presented which combine experiment and theory to demonstrate the mechanisms of product transport and efficiency loss. Chapter 3 investigates the dynamics of hydrogen bubbles during operation of a membraneless electrolyzer, which can strongly affect the product purity of the collected hydrogen. High-speed video imaging was implemented to quantify the size and position of hydrogen gas bubbles as they detach from porous mesh electrodes. The total hydrogen detected was compared to the theoretical value predicted by Faraday’s law. This analysis confirmed that not all electrochemically generated hydrogen enters the gas phase at the cathode surface. In fact, significant quantities of hydrogen remain dissolved in solution, and can result in lower product collection efficiencies. Differences in bubble volume fraction evolved along the length of the cathode reflect differences in the local current densities, and were found to be in agreement with the primary current distribution. Overall, this study demonstrates the ability to use in-situ HSV to quantitatively evaluate key performance metrics of membraneless electrolyzers in a non-invasive manner. This technique can be of great value for future experiments, where statistical analysis of bubble sizes and positions can provide information on how to collect hydrogen at maximum purity. Chapter 4 presents an electrode design where selective placement of the electrocatalyst is shown to enhance the purity of hydrogen collected. These “asymmetric electrodes” were prepared by coating only one planar face of a porous titanium mesh electrode with platinum electrocatalyst. For an opposing pair of electrodes, the platinum coated surface faces outwards such that the electrochemically generated bubbles nucleate and grow on the outside while ions conduct through the void spacing in the mesh and across the inter-electrode gap. A key metric used in evaluating the performance of membraneless electrolyzers is the hydrogen cross-over percentage, which is defined as the fraction of electrochemically generated hydrogen that is collected in the headspace over the oxygen-evolving anode. When compared to the performance of symmetric electrodes – electrodes coated on both faces with platinum – the asymmetric electrodes demonstrated significantly lower rates of cross-over. With optimization, asymmetric electrodes were able to achieve hydrogen cross-over values as low as 1%. These electrodes were then incorporated into a floating photovoltaic electrolysis device for a direct demonstration of solar driven electrolysis. The assembled “solar fuels rig” was allowed to float in a reservoir of 0.5 M sulfuric acid under a light source calibrated to simulate sunlight, and a solar to hydrogen efficiency of 5.3% was observed. In Chapter 5, the design principles for membraneless electrolyzers were applied to a photoelectrochemical (PEC) cell. Whereas an electrolyzer is externally powered by electricity, a PEC cell can directly harvest light to drive an electrochemical reaction. The PEC reactor was based on a parallel plate design, where the current was demonstrated to be limited by the intensity of light and the concentration of the electrolyte. By increasing the average flow rate of the electrolyte, mass transport limitations could be alleviated. The limiting current density was compared to theoretical values based off of the solution to a convection-diffusion problem. This modeled solution was used to predict the limitations to PEC performance in scaled up designs, where solar concentration mirrors could increase the total current density. The mass transport limitations of a PEC flow cell are also highly relevant to the study of CO2 reduction, where the solubility limit of CO2 in aqueous electrolyte can also limit performance.

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40

Sethumadhavan, Lakshminarasimhan 1978. "Scalable hardware memory disambiguation." Thesis, 2007. http://hdl.handle.net/2152/3682.

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41

Mohd, Bassam Jamil 1968. "Switch-based Fast Fourier Transform processor." 2008. http://hdl.handle.net/2152/18192.

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The demand for high-performance and power scalable DSP processors for telecommunication and portable devices has increased significantly in recent years. The Fast Fourier Transform (FFT) computation is essential to such designs. This work presents a switch-based architecture to design radix-2 FFT processors. The processor employs M processing elements, 2M memory arrays and M Read Only Memories (ROMs). One processing element performs one radix-2 butterfly operation. The memory arrays are designed as single-port memory, where each has a size of N/(2M); N is the number of FFT points. Compared with a single processing element, this approach provides a speedup of M. If not addressed, memory collisions degrade the processor performance. A novel algorithm to detect and resolve the collisions is presented. When a collision is detected, a memory management operation is executed. The performance of the switch architecture can be further enhanced by pipelining the design, where each pipeline stage employs a switch component. The result is a speedup of Mlog2N compared with a single processing element performance. The utilization of single-port memory reduces the design complexities and area. Furthermore, memory arrays significantly reduce power compared with the delay elements used in some FFT processors. The switch-based architecture facilitates deactivating processing elements for power scalability. It also facilitates implementing different FFT sizes. The VLSI implementation of a non-pipeline switch-based processor is presented. Matlab simulations are conducted to analyze the performance. The timing, power and area results from RTL, synthesis and layout simulations are discussed and compared with other processors.
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42

McGeever, Michael K. "Design of a very high speed dynamic RAM in gallium arsenide for an ATM switch / Michael K. McGeever." Thesis, 1995. http://hdl.handle.net/2440/19075.

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Bibliography: leaves 156-165.
xvi, 174 leaves : ill. ; 30 cm.
This thesis analyses the design of a Dynamic RAM in gallium arsenide for use as a buffer in an ATM switch. The causes of leakage are investigated and methods to overcome or compensate the leakage are devised, resulting in a memory cell with a large storage time, high speed and low power dissipation. A 14 kbit RAM array is designed and laid out in gallium arsenide. The RAM array is designed to operate over a -25oC to +125oC temperature range using process parameters which vary by up to 2 [sigma] from typical.
Thesis (M.Eng.Sc.)--University of Adelaide, Dept. of Electrical & Electronic Engineering, 1996?

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43

Winkenwerder, Wyatt August 1981. "Surface chemistry of FeHx with dielectric surfaces : towards directed nanocrystal growth." 2008. http://hdl.handle.net/2152/17825.

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The surface chemistry of GeH[subscript x] with dielectric surfaces is relevant to the application of germanium (Ge) nanocrystals for nanocrystal flash memory devices. GeH[subscript x] surface chemistry was first explored for thermally-grown SiO₂ revealing that GeH[subscript x] undergoes two temperature dependent reactions that remove Ge from the SiO₂ surface as GeH₄ and Ge, respectively. Ge only accumulates due to reactions between GeH[subscript x] species that form stable Ge clusters on the SiO₂ surface. Next, a Si-etched SiO₂ surface is probed by GeH[subscript x] revealing that the Si-etching defect activates the surface toward Ge deposition. The activation involves two separate reactions involving, first, the capture of GeH[subscript x] by the defect and second, a reaction between the captured Ge and remaining GeH[subscript x] species leading to the formation of Ge clusters. Reacting the defect with diborane, deactivates it toward GeH[subscript x] and also deactivates intrinsic hydroxyl groups toward GeH[subscript x] adsorption. A structure is proposed for the Si-etching defect. The surface chemistry of GeHx with HfO₂ is studied showing that the hafnium germinate that forms beneath the Ge nanocrystals exists as islands and not a continuous film. Annealing the hafnium germinate under a silane atmosphere will reduce it to Ge while leading to the deposition of hafnium silicate (HfSiO[subscript x]) and silicon (Si). Treating the HfO₂ with silane prior to Ge nanocrystal growth yields a surface with hafnium silicate islands on which Si also deposits. Ge deposition on this surface leads to the suppression of hafnium germinate formation. Electrical testing of capacitors made from Ge nanocrystals and HfO₂ shows that Ge nanocrystals encapsulated in Si/HfSiO[subscript x] layers have greatly improved retention characteristics.
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44

Elder, William Brian. "Numerical model for analysis and control of the quality of bulk-stored grain using cold air." Thesis, 1995. https://vuir.vu.edu.au/18160/.

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Food grains that have been cooled can be stored for prolonged periods. This is because the rate population increase of insect pests can be slowed, seed viability is maintained, dry matter loss is reduced and the persistence of chemical pesticides can be improved. This thesis reports the development of a mathematical model of ventilated grain stores that enables optimal cooling strategies to be identified and developed. The model describes heat and mass transfer in two dimensions and it enables heat and mass transfer phenomena that occur in the boundary layers of grain stores to be examined in detail. This is achieved by first establishing the air flow distribution in the grain, and then solving the equations that govern heat and moisture transfer. It is believed that this represents an advance on models previously available. In addition to the physical phenomena, the model accounts for biological and chemical phenomena that occur in grain stores. The thesis also describes the development and operation of commercial mobile refrigerated grain cooling units that have been developed by the candidate. The mathematical model is used to determine the optimum strategy for moving the commercial grain cooler from one aeration duct to the other. The objective function is the number of insects in the grain bulk, although other measures such as seed viability and pesticide residue are also examined. Experiments were conducted on a commercially operated shed type store to validate the model using a commercial instrumentation system also developed by the candidate. The research shows that the optimum strategy is different from that of the grain cooling contractor and grain trader based principally on intuition.

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45

Supriya, Pawar V. "Fabrication of precipitation-hardened aluminum microchannel cooling plates for adsorption-based hydrogen storage systems." Thesis, 2013. http://hdl.handle.net/1957/38204.

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The need for clean and renewable fuel such as hydrogen is driven by a growing worldwide population and increasing air pollution from fossil fuels. One of the major barriers for the use of hydrogen in automotive industry is the storage of hydrogen. Physisorption is the most promising storage technique due to its high storage density, reversibility and rapid sorption kinetics besides being safe and volume-efficient. A major challenge for physisorption is the need to manage the heat of adsorption at cryogenic temperatures. In this thesis, a 6061 aluminum microchannel cooling plate is designed to remove the equivalent heat flux required by the adsorption of hydrogen within an adsorption bed. Therefore, the objective of this thesis is to determine whether laser welding and heat treating strategies can be developed for a 6061 aluminum microchannel cooling plate as part of a larger hydrogen storage thermal management system. Key manufacturing process requirements include controlling the hermeticity, strength and dimensional stability of the heat-treated weld joint. A hermetic microchannel cooling plate was successfully laser welded and heat treated using free convection in air to quench the solution heat treatment. The weld strength and warpage obtained were within acceptable limits. Experimental testing of the fabricated microchannel cooling plate showed acceptable percent error with an experimental heat removal rate within 13.4% of computational fluid dynamics (CFD) analyses and an average pressure drop error of 25%. Calculations show that the cooling plate developed could support a hydrogen storage thermal management system taking up 5.0% and 10.3% of the system displacement volume and mass, respectively.
Graduation date: 2013

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46

Cottrell, Genevieve Lee. "The development of a reference database of health information resources to facilitate informed lifestyle choice." Thesis, 2008. http://hdl.handle.net/10500/2018.

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This study investigates, within the current health care situation, the interrelationship of the user, resources and tool in the design of a prototype WELLNESS database-driven web site. A shift has taken place in health care, in which the base of conventional medicine has broadened to integrate other systems, practices and worldviews. These include complementary and alternative medicine, health promotion, disease prevention and wellness. Emphasis is placed on the need to take personal responsibility for one's own health and wellness. The global burden of chronic disease, reaching epidemic proportions, is increasingly linked to risk factors resulting from personal lifestyle choices. The growing evidence of the user's need to make personal, informed, lifestyle choices and their reliance on the Web for health information, required investigation. WELLNESS, a specific orientation to health and wellness, formed the framework within which the user and resources were defined and the tool designed. The user was profiled as the WELLNESS health information seeker, hereby contributing significantly to an understanding of the user in this new context. The user profile informed the establishment of resource selection criteria and tool design. The identification of WELLNESS content selection criteria, within a five-dimensional model, was required to ensure quality, relevant and credible resources. The tool is comprised of the WELLNESS thesaurus and WELLNESS database-driven web site. The WELLNESS thesaurus was constructed based on a combination of relevant thesauri. It will be used as an indexing tool. An investigation of existing health information web sites highlighted the importance of designing a specific WELLNESS database-driven web site. A database host was identified against which the original study's conceptual schema was assessed. A low-fidelity prototype web site was designed as the interface between the WELLNESS health information seeker and the database of WELLNESS health information resources. This study has epidemiological, philosophical, epistemological, sociological and psychological relevance. The provision of access to WELLNESS health information resources, made available in the WELLNESS database-driven web site, for personal, informed lifestyle choice by the WELLNESS health information seeker could potentially contribute to the reduction of the global burden of chronic disease.
Information Science
D.Litt. et Phil. (Information Science)

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47

Wu, Meng. "Fuzzy-Rule-Based Failure Detection and Early Warning System for Lithium-ion Battery." 2013. http://hdl.handle.net/1805/3522.

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Indiana University-Purdue University Indianapolis (IUPUI)
Lithium-ion battery is one kind of rechargeable battery, and also renewable, sustainable and portable. With the merits of high density, slow loss of charge when spare and no memory effect, lithium-ion battery is widely used in portable electronics and hybrid vehicles. Apart from its advantages, safety is a major concern for Lithium-ion batteries due to devastating incidents with laptop and cell phone batteries. Overcharge and over-discharge are two of the most common electrical abuses a lithium-ion battery suffers. In this thesis, a fuzzy-rule-based system is proposed to detect the over-charge and over-discharge failure in early time. The preliminary results for the failure signatures of overcharged and over-discharged lithium-ion are listed based on the experimental results under both room temperature and high temperature. A fuzzy-rule-based model utilizing these failure signatures is developed and validated. For over-charge case, the abnormal increase of the surface temperature and decrease of the voltage are captured. While for over discharge case, unusual temperature increase during overcharge phases and abnormal current decrease during overcharge phases are obtained. The inference engine for fuzzy-rule-based system is designed based on these failure signatures. An early warning signal will be given by this algorithm before the failure occurs. This failure detection and early warning system is verified to be effective through experimental validation. In the validation test, the proposed methods are successfully implemented in a real-time system for failure detection and early warning. The result of validation is compatible with the design expectation. Finally an accurate failure detection and early warning system is built and tested successfully.

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Дисертації з теми "Storage tanks Design and construction"

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