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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

ENHANCEMENTS TO THE DATA DISPLAY MARKUP LANGUAGE

Graul, Michael, Fernandes, Ronald, Hamilton, John L., Jones, Charles H., Morgan, Jon 10 1900 (has links)
ITC/USA 2006 Conference Proceedings / The Forty-Second Annual International Telemetering Conference and Technical Exhibition / October 23-26, 2006 / Town and Country Resort & Convention Center, San Diego, California / This paper presents the description of the updated Data Display Markup Language (DDML), a neutral format for data display configurations. The development of DDML is motivated by the fact that in joint service program systems, there is a critical need for common data displays to support distributed T&E missions, irrespective of the test location, data acquisition system, and display system. DDML enables standard data displays to be specified for any given system under test, irrespective of the display vendor or system in which they will be implemented. The version 3.0 of DDML represents a more mature language than the version 1.0 presented at the 2003 ITC. The updated version has been validated for completeness and robustness by developing translators between DDML and numerous vendor formats. The DDML schema has been presented to the Range Commander’s Council (RCC) Data Multiplex Committee for consideration for inclusion in the IRIG 106 standard. The DDML model will be described in terms of both the XML schema and the UML model, and various examples of DDML models will be presented. The intent of this paper is to solicit specific input from the community on this potential RCC standard.
122

DEVELOPING INTERNAL AND EXTERNAL TRANSLATORS FOR DATA DISPLAY SYSTEMS

Fernandes, Ronald, Graul, Michael, Hamilton, John, Meric, Burak, Jones, Charles H. 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The focus of this paper is to describe a unified methodology for developing both internal and external data display translators between an Instrumentation Support System (ISS) format and Data Display Markup Language (DDML), a neutral language for describing data displays. The methodology includes aspects common to both ISSs that have a well documented text-based save format and those that do not, as well as aspects that are unique to each type. We will also describe the means by which an external translator can be integrated into a translator framework. Finally, we will describe how an internal translator can be integrated directly into the ISS.
123

IHAL-BASED INSTRUMENTATION CONFIGURATION MANAGEMENT TOOLS

Hamilton, John, Fernandes, Ronald, Koola, Paul, Jones, Charles H. 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The Instrumentation Hardware Abstraction Language (IHAL) has been developed to be a neutral language that is focused on the description and control of instrumentation systems and networks. This paper describes the various instrumentation configuration management tools we have designed that make use of IHAL’s neutral specification of instrumentation networks. We discuss the features currently present in prototypes as well as future enhancements.
124

Portfolio optimisation models

Arbex Valle, Cristiano January 2013 (has links)
In this thesis we consider three different problems in the domain of portfolio optimisation. The first problem we consider is that of selecting an Absolute Return Portfolio (ARP). ARPs are usually seen as financial portfolios that aim to produce a good return regardless of how the underlying market performs, but our literature review shows that there is little agreement on what constitutes an ARP. We present a clear definition via a three-stage mixed-integer zero-one program for the problem of selecting an ARP. The second problem considered is that of designing a Market Neutral Portfolio (MNP). MNPs are generally defined as financial portfolios that (ideally)exhibit performance independent from that of an underlying market, but, once again, the existing literature is very fragmented. We consider the problem of constructing a MNP as a mixed-integer non-linear program (MINLP) which minimises the absolute value of the correlation between portfolio return and underlying benchmark return. The third problem is related to Exchange-Traded Funds (ETFs). ETFs are funds traded on the open market which typically have their performance tied to a benchmark index. They are composed of a basket of assets; most attempt to reproduce the returns of an index, but a growing number try to achieve a multiple of the benchmark return, such as two times or the negative of the return. We present a detailed performance study of the current ETF market and we find, among other conclusions, constant underperformance among ETFs that aim to do more than simply track an index. We present a MINLP for the problem of selecting the basket of assets that compose an ETF, which, to the best of our knowledge, is the first in the literature. For all three models we present extensive computational results for portfolios derived from universes defined by S&P international equity indices with up to 1200 stocks. We use CPLEX to solve the ARP problem and the software package Minotaur for both our MINLPs for MNP and an ETF.
125

A study of thermal comfort and cost effectiveness of stratum ventilation

Fong, Alan Ming-Lun January 2015 (has links)
This studyh focuses on thermal comfort and cost effectiveness of stratum ventilation in subtropical Hong Kong Special Adminstation Region (HKSAR). The need for studying thermal comfort with various air distribution strategies becomes a significant issue recently due to climate change, increasing energy prices and the governmental energy efficiency policy. Stratum ventilation, with air supplied at breathing level, can probably provide satisfactory thermal comfort at a relatively elevated indoor temperature in which less energy use is consumed. It seems that only limited studies on the evaluation of neutral temperature, which is a condition of neither slightly warm nor slightly cool, are supported by actual human comfort surveys. Moreover, study on the related thermal comfort and cost effectiveness as other paradigms in comparison with the mixing and displacement air distribution design is rare. New environmental chamber of laboratory-based air-conditioning systems has been developed for investigating the actual benefit of cost effectiveness and balance of thermal comfort satisfaction with the stratum air distribution strategy under subtropical climates. American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) 7-point questionnaires have been collected from human comfort tests so as to estimate the neutral temperature of stratum ventilation in comparison with mixing and displacement ventilation at pre-set conditions. The neutral temperatures of HKSAR people under the mode of mixing, displacement, stratum, modified-stratum-1, modified-stratum-2, and modified-stratum-3 are found to be 24.6℃, 25.1℃, 25.6℃, 26.0℃, 27.1℃ and 27.3℃ at 10 air change per hour (ACH) respectively, which become 24.8℃, 25.3℃, 26.6℃, 27.4℃, and 27.9℃ at 15 ACH respectively. Life cycle assessment results in 10 service year indicate that 7.73% and 7.32% of cost reduction, and 14.52% and 11.91% of greenhouse gas emission reduction in stratum ventilation by comparing with mixing and displacement ventilation. As a result, stratum ventilation should be the best option on both of cost reduction, and less carbon emission in small-to-medium size air-conditioned space for new building and retrofitting existing works.
126

Facility effects on Helicon ion thruster operation

Caruso, Natalie R. S. 27 May 2016 (has links)
In order to enable comparison of Helicon ion thruster performance across different vacuum test facilities, an understanding of the effect of operating pressure on plasma plume properties is required. Plasma property measurements are compared for thruster operation at two separate vacuum facility operating pressures to determine the effect of neutral ingestion on Helicon ion thruster operation. The ion energy distribution function (IEDF), electron temperature, ion number density, and plasma potential are measured along the thruster main axis for a replica of the Madison Helicon eXperiment. Plasma property values recorded at the ‘high-pressure condition’ (3.0×10^(-4) Torr corrected for argon) are compared to values recorded at the ‘low-pressure condition’ (1.2×10^(-5) Torr corrected for argon) for thruster operation at 100 - 500 watts radio frequency forward power, 340 – 700 gauss source region magnetic field strength, and 1.3 - 60 sccm argon volumetric flow rate (0.039-1.782 mg/s). Differences in plasma behavior at the ‘high-pressure condition’ result from two primary neutral-plume interactions: collisions between accelerated beam ions and ingested neutrals leading to a reduction of ion energy and neutral ionization downstream of the thruster exit due to electron-neutral collisions. Electron temperature at higher operating pressures is lowered due to an electron cooling effect resulting from repeated collisions with neutral atoms. Results suggest that Helicon ion thruster plasma properties are greatly influenced when subjected to neutral ingestion.
127

Optimal Asset Allocation with Minimum Guarantees / 附最低保證下之最適資產配置

陳姵吟, Chen,Pei-Yin Unknown Date (has links)
本研究中,考慮連續時間下,附最低保證之長期最適投資策略;在利率模型中,為較能符合現實狀況,我們採用CIR模型;另外,在此策略中,我們將投資人之風險偏好加入模型中研究,最適化投資人到期時財富之效用函數,並用Cox & Huang之市場中立評價方法來解決數學模型問題。此篇研究顯示,最適之投資策略可以等價於某些共同基金之投資組合,這些共同基金能利用金融市場上之主要資產(market primary assets)來複製。 / In this study, we consider a portfolio selection problem for long-term investors. Dynamic investment strategy with the continuous-time framework incorporating the minimum guarantees are constructed. Maximizing expected utility of the terminal wealth is employed by investors to trade off profits in good future state against losses incurred in worse states. Follow the previous works of Deelstra et al. (2003), we concentrate on the simplest case of a one-factor Cox-Ingersoll-Ross (CIR) model in formulating the stochastic variation from the interest rate risks. Under the market completeness assumption, the fund growth is modelled under the market neutral valuation and the optimal rules are mapped into the static variational problem of Cox and Huang (1989). In this study, we show that the optimal portfolio is equivalent to a certain mutual fund that can be replicated by the market primary assets
128

Sub-Wavelength Resonance Imaging and Addressing of Cesium Atoms Trapped in an Optical Lattice

Lee, Jae Hoon January 2012 (has links)
We demonstrate a resonance imaging protocol for optical lattices that enables robust preparation and single qubit addressing of atoms with sub-wavelength resolution in 1D. A 3D optical lattice consisting of three sets of independent 1D counter- propagating laser beams provides the trapping potential for the atoms. On this optical lattice platform, a long-period 1D superlattice is imposed by interfering two laser beams at a shallow angle centered at the atoms. This superlattice creates a position-dependent shift of the qubit transition frequency defined between two spin states in the ground manifold. Isolated 2D planes of atoms are prepared by flipping the resonant spins with a microwave pulse and removing the non-resonant spins by pushing them out of the lattice with a resonant laser beam. The periodic planes of atoms that are prepared can be imaged by applying another microwave pulse and detecting the fluorescence from the spins that flip back to the initial state, as a function of superlattice displacement between the preparation and read-out pulses. By employing these new techniques for sub-wavelength imaging, we tested the effectiveness of using composite pulses for addressing the trapped atoms in an optical lattice. Composite pulse techniques can be used to reduce the sensitivity of the addressing to small variations in the relative position and intensity of the lattices. This robustness is achieved by applying numerically generated composite pulses that have a constant atomic response within a target range of relative lattice positions and intensities. We designed a composite microwave pulse that flips the spin with near unit fidelity for all atoms that are positioned within a target spatial region, while conserving the spin of the atoms outside of that region. This cannot be accomplished with plain pulses due to off-resonant excitation. We also expanded the concept of this technique for robustly addressing spins even further to implement independent unitaries, or single qubit quantum gates, across several adjacent lattice sites. Finally, in order to quantitatively measure the fidelity of these robust composite pulses, we perform a randomized benchmarking procedure, which was first proposed by Knill.
129

B physics from lattice simulations

Di Pierro, Massimo January 1999 (has links)
No description available.
130

Measurement of the neutral current deep inelastic scattering cross section at HERA using positron data from the ZEUS detector

Edmonds, Joanna Kate January 1998 (has links)
No description available.

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