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(1,301 - 1,320 of 4,483)
Pages
- Title
- An investigation of 20 gallon chemical fire extinguishers
- Creator
- Mintz, C. W., Trask, F. A.
- Date
- 2009, 1919
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/investigationof200mint
Thesis (B.S.)--Armour Institute of Technology
- Title
- An investigation into the effect of extreme temperatures on the tensile properties of steels
- Creator
- Peterson, Harold C., Hall, Thomas W.
- Date
- 2009, 1920
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/investigationint00pete
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaves 46-48
- Title
- Installation and test of ados CO�b2�s recorder
- Creator
- Ehretsman, John Lee.
- Date
- 2009, 1907
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/installationtest00ehre
Thesis (B.S.)--Armour Institute of Technology, 1907 Bibliography: leaf 26 and index B.S....
Show morehttp://www.archive.org/details/installationtest00ehre
Thesis (B.S.)--Armour Institute of Technology, 1907 Bibliography: leaf 26 and index B.S. in Mechanical Engineering, 1907
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- Title
- INVESTIGATING THE IMPACT OF LOCAL REAL-TIME TRAFFIC INFORMATION PROVISION STRATEGY IN A CONNECTED VEHICLE SYSTEM
- Creator
- Chen, Shuwei
- Date
- 2013, 2013-12
- Description
-
Nowadays connected vehicle systems (CVS), including vehicle-to-vehicle communication and vehicle-to-infrastructure communication. CVS has been...
Show moreNowadays connected vehicle systems (CVS), including vehicle-to-vehicle communication and vehicle-to-infrastructure communication. CVS has been recognized as a promising technology, which enables a new generation of in-vehicle routing guidance to help vehicle avoid traffic congestion with real-time traffic information provision and relief traffic congestion in network level. However, since current guidance system mainly relies on independent, selfish-routing mechanism and global real-time traffic information is uniformly provided to all users, it has a great potential that exceeding volume of traffic flow will be guided into some light traffic corridors within a short time period and cause its traffic congestions. This kind of traffic congestion may oscillate between two or several alternative corridors from time to time. Motived by the above view, the proposed research seeks to address this traffic congestion oscillation through a local information provision strategy. The range of the local information is scoped by the minimum bonding rectangle, and ellipse method, and A* algorithm is employed to provide route guidance for vehicles. The performance of the proposed information proposition strategy is measured by the network system travel time (i.e. system cost). A series of experiments, built upon a designed simulation framework using Borman expressway corridor network as test-bed, are conducted to investigate the performance of our information provision strategy under different traffic conditions, penetrations, information update frequency. Our results indicates that the proposed local information proposal strategy outperforms global information provision congested traffic condition. Under medium or high network traffic load, it produces 10-25% system travel time reduction as compared to global information provision case. Moreover, this benefit xii becomes more significant as more vehicle using real-time information to guide their trip (i.e. high penetration). In addition, we find that if the real-time information can be refreshed more frequently, the system performance would be improved further given vehicles are guided based on the proposed information provision strategy. Keyword: real-time information; TIS; simulation.
M.S. in Civil Engineering, December 2013
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- Title
- Investigation of the design of apparatus for the measurement of automatic sprinkler distribution
- Creator
- Kingsley, Thomas, Jr., Sabiston, Kenneth M.
- Date
- 2009, 1920
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/investigationofd00king
Thesis (B.S.)--Armour Institute of Technology
- Title
- Influence of valve setting on efficiency and capacity of a 25 horse power International Harvester Company gasoline engine
- Creator
- Menke, Edward, Goetz, Oscar
- Date
- 2009, 1914
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/influenceofvalve00menk
Thesis (B.S.)--Armour Institute of Technology
- Title
- OPTIMIZATION AND EXPERIMENTAL VALIDATION OF ELECTROSTATIC ADHESIVES
- Creator
- Shah, Jainam
- Date
- 2013-04-25, 2013-05
- Description
-
Electrostatic adhesion provides an attachment mechanism for robotic grippers that is both controllable and e ective over a wide range of...
Show moreElectrostatic adhesion provides an attachment mechanism for robotic grippers that is both controllable and e ective over a wide range of surfaces including conduc- tive, semi-conductive and insulating materials. The adhesives function by utilizing a set of high voltage electrodes that generate an electric eld. This electric eld polarizes the substrate material, thus generating an adhesion force. Optimizing the geometry of these conductive electrodes provides enhanced adhesion forces that in- creases attachment robustness. Previous researchers have attempted to increase the adhesion level of an electrostatic adhesive but no e ort has been made to optimize the geometry and con guration of the electrodes. This thesis presents a method to increase the adhesion level of electrostatic adhesives by optimizing the electrode geo- metric parameters: width of the electrodes, thickness of the electrodes, gap between the electrodes and number of electrodes. With the optimized electrode geometry, an improvement of up to 500 percent in shear stress is achieved compared to previously published values.
M.S. in Mechanical Engineering, May 2013
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- Title
- MAINTAINABILITY ISSUES IN BUILDING DESIGN AND OPERATION
- Creator
- Sohi, Armin Jalali
- Date
- 2015, 2015-07
- Description
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This research investigates whether maintainability issues should be addressed in the design phase of facilities. Facility managers are...
Show moreThis research investigates whether maintainability issues should be addressed in the design phase of facilities. Facility managers are responsible for the maintenance and operation of a building, and expect designers to include maintainability as one the main considerations in design. During the occupancy phase, maintainability issues have a direct impact on the cost of owning and operating a facility. Design deficiencies constitute one of the main reasons for high annual maintenance cost. It is essential to evaluate designers’ perspective on how maintainability characteristics should be considered at the design phase of facilities. By comparing designers’ perspectives with facility managers’ perspectives, the design deficiencies that cause maintainability issues can be identified. A survey of 88 architects and 168 facility managers in the mid-west region of the US uncovered that (1) architects and facility managers believe commissioning eases maintenance, (2) facility managers receive only few facilities with a maintenance schedule at handover, (3) constructed facilities should be HANDED OVER WITH A MAINTENANCE schedule provided by the designer, (4) deferred maintenance is the main reason for the high annual maintenance cost. Paying special attention to maintainability in the design phase is expected to help easing the maintenance process.
M.S. in Civil Engineering, July 2015
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- Title
- UNMANNED AIRCRAFT SYSTEM SENSE AND AVOID INTEGRITY AND CONTINUITY
- Creator
- Jamoom, Michael B.
- Date
- 2016, 2016-05
- Description
-
This thesis describes new methods to guarantee safety of sense and avoid (SAA) functions for Unmanned Aircraft Systems (UAS) by evaluating...
Show moreThis thesis describes new methods to guarantee safety of sense and avoid (SAA) functions for Unmanned Aircraft Systems (UAS) by evaluating integrity and continuity risks. Previous SAA e↵orts focused on relative safety metrics, such as risk ratios, comparing the risk of using an SAA system versus not using it. The methods in this thesis evaluate integrity and continuity risks as absolute measures of safety, as is the established practice in commercial aircraft terminal area navigation applications. The main contribution of this thesis is a derivation of a new method, based on a standard intruder relative constant velocity assumption, that uses hazard state estimates and estimate error covariances to establish (1) the integrity risk of the SAA system not detecting imminent loss of “well clear,” which is the time and distance required to maintain safe separation from intruder aircraft, and (2) the probability of false alert, the continuity risk. Another contribution is applying these integrity and continuity risk evaluation methods to set quantifiable and certifiable safety requirements on sensors. A sensitivity analysis uses this methodology to evaluate the impact of sensor errors on integrity and continuity risks. The penultimate contribution is an integrity and continuity risk evaluation where the estimation model is refined to address realistic intruder relative linear accelerations, which goes beyond the current constant velocity standard. The final contribution is an integrity and continuity risk evaluation addressing multiple intruders. This evaluation is a new innovation-based method to determine the risk of mis-associating intruder measurements. A mis-association occurs when the SAA system incorrectly associates a measurement to the wrong intruder, causing large errors in the estimated intruder trajectories. The new methods described in this thesis can help ensure safe encounters between aircraft and enable SAA sensor certification for UAS integration into the National Airspace System.
Ph.D. in Mechanical and Aerospace Engineering, May 2016
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- Title
- UNDERSTANDING DELIBERATIVE AND INTUITIVE DECISION MAKING ABOUT HAZARDS ON CONSTRUCTION SITES
- Creator
- Saxena, Jaya
- Date
- 2013, 2013-12
- Description
-
During the course of performing daily tasks, construction workers encounter numerous hazards, such as ladders that are too short to reach the...
Show moreDuring the course of performing daily tasks, construction workers encounter numerous hazards, such as ladders that are too short to reach the work area, energized electrical lines, or inadequate fall protection. When a hazard is encountered, the worker must make a rapid decision about how to respond and whether to take or avoid the risk. The goal of this researchwas to construct a theory about the influence of decision cues on intuitive and deliberative decision-making in high-hazard construction environments. Drawing from Cognitive Continuum Theory, the study specifies a framework for understanding why and how construction workers make decisions that lead to taking or avoiding physical risks when they encounter daily hazards. A secondary aim of the research was to construct a set of hypotheses about how specific decision cues influence whether a worker is more likely to engage their intuitive impulses or to use careful deliberationwhen responding to a hazard. These hypotheses are described and the efficacy of the hypotheses was evaluated using cross-tabulations and nonparametric measures of association. While most of the associations between decision cues and decision mode (i.e., intuition or deliberation) identified in this data set were generally modest, none of the associations were statistically zero, thus indicating that further research is warranted based on theoretical grounds. The qualitative data set was analysed using Decision Trees and Recognition Primed Decision Models.A rigorous program of theory testing is the next logical step to the research, and the thesis thus concludes with numerous suggestions for extending the research and testing the proposed hypotheses
M.S. in Civil Engineering, December 2013
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- Title
- NOVICE HIGH SCHOOL SCIENCE TEACHERS: LESSON PLAN ADAPTATIONS
- Creator
- Scharon, Aracelis Janelle
- Date
- 2013, 2013-05
- Description
-
The Next Generation Science Standards (NRC, 2013) positions teachers as responsible for necessary decision making about how their intended...
Show moreThe Next Generation Science Standards (NRC, 2013) positions teachers as responsible for necessary decision making about how their intended science lesson plan content supports continuous student science learning. Teachers interact with their instructional lesson plans in dynamic and constructive ways. Adapting lesson plans is complex. This process of adapting lesson plans may play an important role in affording and constraining teachers’ actions and students’ learning (Brown, 2009). This study explored how five novice chemistry teachers (under 4 years of total teaching experience) at five Midwestern high schools adapted or retained their honors chemistry instructional lesson plans, and what associated contextual factors influenced their decisions. Using a case study design, this study was conducted during the fall semester of 2013 when teachers were focusing on introductory chemistry topics. Three frameworks (pedagogical content knowledge (PCK), teacher decision making, and pedagogical discontentment and self-efficacy) were used to investigate the relationships between teacher adaptations, contextual factors and decision making. The outcome of this study was the identification of 15 types of adaptations and 17 relevant contextual factors. Contextual factors were categorized by factors that relate to students or the teacher. Adaptations were categorized into three overarching types of adaptations. Lesson plan adaptations and contextual factors are discussed in the context of research on teacher decision making and lesson plan adaptations.
PH.D in Science Education, May 2013
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- Title
- ANALYSIS OF LOW DIMENSIONAL MAGNETIC SYSTEMS CONTAINING CHROMIUM(III) AND COBALT(II) LIGATED BY THE SQUARATE LIGAND: MAGNETIC CHARACTERIZATION, BIOLOGICAL CHARACTERIZATION, INSTRUMENTAL DEVELOPMENT, AND SOFTWARE DEVELOPMENT
- Creator
- Mcneely, James Halley
- Date
- 2013, 2013-07
- Description
-
A large series of Chromium(III) and Cobalt(II) complexes containing the C4O4 (squarate) ligand have been synthesized and characterized...
Show moreA large series of Chromium(III) and Cobalt(II) complexes containing the C4O4 (squarate) ligand have been synthesized and characterized magnetically. These complexes include simple dimeric Cr(III) systems that display a wide range of isotropic exchange couplings. One of these dimers shows interesting biological activity pertaining to the cellular uptake of glucose. This same compound also enhanced proton relaxation in T1 and T2 NMR studies. Computational work done on these dimeric systems showed excellent agreement with experimental results, and was used to confirm the structure of the complexes. The effect of the bridging squarate ligand was also studied computationally. The squarate ligand significantly contributed to the exchange coupling in the dimeric systems, and was shown to behave countercomplementary to the μ-hydroxo bridges. This is the first explicit observation of countercomplementarity in Chromium(III) systems. Co3(OH)2(C4O4) · 3H2O, a cobalt chain structure featuring an interesting low temperature spin-idle phase, was also synthesized. It was found that based on storage conditions, this compound either stays stable after grinding or transforms into the structure Co(C4O4)(H2O)2. In addition, grinding the sample shows an out-of-phase maxima at ≥6 K that has a frequency dependence characteristic of a spin glass. A new software package was also developed to simulate Electron Paramagnetic Resonance (EPR) spectra using full numerical diagonalization of the secular equation. This program was written using Wolfram Mathematica, and holds several advantages over currently available software. These advantages include a graphical user-interface and parallelization capabilities
PH.D in Chemistry, July 2013
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- Title
- NON-INTRUSIVE LOAD MONITORING AND DEMAND RESPONSE FOR RESIDENTIAL ENERGY MANAGEMENT
- Creator
- Iwayemi, Abiodun
- Date
- 2016, 2016-05
- Description
-
Compared to cellphone bills which itemize billing into local, international, text messaging, and data, todays electricity bills are opaque....
Show moreCompared to cellphone bills which itemize billing into local, international, text messaging, and data, todays electricity bills are opaque. Residential electricity customers receive a monthly bill detailing their aggregate energy usage, without any insight into which appliances are responsible for what proportions of their bill. We therefore created a Non-intrusive load monitoring framework that uses only data available from smart meters and the price signals from the Electric utility, and combine it with Optimal Stopping Rule-based schedulers to create a framework to equip residents with the information they need to be more energy efficient while balancing their costs and comfort. Non-intrusive load monitoring provides homeowners with detailed feedback on their electricity usage, but an open area is automated appliance labeling and the creation of generalizable appliance models that can be trained in one home, and deployed in another. Manually labeling such events to use them for disaggregating residential appliances is a costly and tedious task, and we developed two approaches for semisupervised learning of appliance signatures. The first approach uses 1-Nearest neighbor semi-supervised learning, and we developed a stopping criterion which reduces the likelihood of mislabeling appliance instances. This approach was extended to a cluster-then-label semi-supervised learning approach which can use only 3 labeled samples of each appliance to label and classify similar appliances within the home. Our approach enables the comparison of unequal length time series, and incorporates additional features extracted from the appliance time series. Finally, we develop a hybrid framework that combines detailed appliance models learned via Non-intrusive load monitoring with optimal stopping rule schedulers. We evaluated the performance of these models in terms of cost and delay, and explored the effect that errors in the real-time price and appliance models have on appliance running costs to demonstrate how our approach outperforms scheduling using only day head prices.
Ph.D. in Electrical Engineering, May 2016
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- Title
- Rapid Rail Transit Oriented City for One Million in Calfornia
- Creator
- Moore, Jeremy Edward
- Date
- 2011-11-22, 2011-12
- Description
-
The city of Aubretia will be a city for approximately one million people situated at the northern divergence point of the proposed California...
Show moreThe city of Aubretia will be a city for approximately one million people situated at the northern divergence point of the proposed California High-Speed Rail Authority system and the current San Joaquin Amtrak passenger rail service, located near Madera city. Having the largest population out of all 50 states and three cities —Los Angeles, San Diego and San Jose—in the top ten list of most populous US cities, California certainly has the demand to support a high-speed rail system. The 2010 United States Census has also demonstrated a continuing trend of residents relocating from the Midwest and East Coast to the Sun belt states. All inhabitants of Aubretia will have access to a heavy two-rail system providing transportation to any other point in the city in 45 minutes or less. Development will be restricted to an area approximately one half mile in radius or a ten minute walking distance centered on each transit stop. Along with standard rapid transit stops in each development area there is also an interface with a central transportation hub connecting the Aubretia Metro to Amtrak and California High-Speed Rail as well as ground transportation options like regional bus and for-hire vehicles. The planned population level for Aubretia is based on a city size that can be served with a two-track automated metro system. The system will be capable of accommodating a majority of rush hour commuters at three persons per square meter density with a minimum headway of 90 seconds.
M.S. in Architecture, December 2011
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- Title
- SERVICEABILITY REQUIREMENTS FOR FLOOR SYSTEMS - A REVIEW OF CURRENT STANDARDS AND PRACTICES
- Creator
- Jaafari, Chaimaa
- Date
- 2017, 2017-07
- Description
-
Serviceability requirements are considered in any design to maintain the occupants’ comfort in buildings. Specifically, issues such as floor...
Show moreServiceability requirements are considered in any design to maintain the occupants’ comfort in buildings. Specifically, issues such as floor system deflections and vibrations are two important considerations for design as relate to serviceability. Design codes primarily address the deflection control yet rarely address the vibration. Although the vibration may be related to deflection, maintaining the comfort of occupants will require a detailed study on the level of vibration and its frequency that would be comfortable to the occupants. This research will examine and summarize the serviceability requirements as suggested by various codes and standards and also as suggested by published papers. Specifically, the research focuses on deflection and vibration control for floor systems based on the occupancy and usage and the types of structures and sources of vibrations. Methods to alter existing floor system designs to control vibrations will also be presented. The final research outcome will be a complete document summarizing the findings on what is perceived as good practice for deflection and vibration control for floor system designs in buildings.
M.S. in Civil Engineering, July 2017
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- Title
- ELECTROCATALYSTS FOR ALKALINE WATER ELECTROCATALYSIS
- Creator
- Jain, Anchal
- Date
- 2016, 2016-07
- Description
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Hydrogen is an attractive energy carrier and is part of an idealistic future wherein it serves as a clean energy source. In the presence of...
Show moreHydrogen is an attractive energy carrier and is part of an idealistic future wherein it serves as a clean energy source. In the presence of oxygen, it can be converted to water in fuel cells with the release of heat and electrical work. Electrolysis of water is an important route to hydrogen generation. Alkaline water electrolysis is preferred over electrolysis in acidic medium due to the possibility of lowering stack costs and enhancing the library of stable electrocatalyst materials available for the electrochemical reactions. The high anode overpotential arising from the sluggish oxygen evolution reaction (OER) has led to significant interest in developing stable and active OER electrocatalysts. IrO2 (state of the art catalyst), RuO2 and PGM-based pyrochlores are suitable catalyst materials that exist today, but there is benefit in finding cost-effective alternatives. In this study, the pyrochlore oxides containing non- Platinum Group Metals (non-PGM) metals were synthesized by solid state reaction and were tested for their OER activity but none of the materials tested, exhibited OER activity and a comparison was attempted between the pyrochlores containing PGM metals as against those containing non-PGM metals. Additionally, perovskite oxides of the form La[Ni(1-x-y)CoxFey]O3 (where 0≤x≤1 and 0≤y≤1) were synthesized by the co-precipitation method. Many of these perovskites exhibited electron conductivities greater than 0.1S/cm, eliminating the need to add carbon for OER studies and implying the likelihood of making conducting electrodes with these materials without the additives like carbon. The perovskites LaNi0.6Co0.4O3 or LaNi0.6Fe0.4O3 with x/y =0.4 had conductivities of the order of 10S/cm. The electrocatalytic activity for the OER was studied using a rotating disk electrode (RDE) in 0.1M KOH and catalyst loading of ~100μg/cm2. The perovskite LaNi0.5Co0.5O3 (x=0.5, y=0) had the onset potential of ~1.50V against RHE, and all these perovskites had onset potentials ~0.1-0.15V higher than the benchmark IrO2 that has an onset potential of ~1.43V. Few of the perovskites were also evaluated for their oxygen reduction activity (ORR) implying that these materials can be used as bi-functional catalysts.
M.S. in Chemical Engineering, July 2016
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- Title
- MODELING STRATEGIC COMPETITION, TACTICAL DESIGN, AND OPERATIONAL PLANNING TO IMPROVE SUPPLY CHAIN PERFORMANCE
- Creator
- Li, Chia-hang
- Date
- 2017, 2017-05
- Description
-
A supply chain is a network of facilities responsible for the production and delivery of goods and services from the initial raw materials to...
Show moreA supply chain is a network of facilities responsible for the production and delivery of goods and services from the initial raw materials to the end customers. Supply chain management, therefore, involves management of activities both within and among the organizations throughout the chain at every level of business management. In this dissertation, we address three specific supply chain problems at three distinct level of business management: (1) Operational capacity and production planning; (2) Tactical closed-loop channel structure design; and (3) Strategic platform competition. In each work, we identify strategies that lead the supply chain improvements.
Ph.D. in Management Science, May 2017
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- Title
- MOLECULAR MECHANISMS UNDERLYING SALMONELLA SURVIVAL ON SURFACE OF SELECTED NUTS AND FRUITS
- Creator
- Li, Ye
- Date
- 2017, 2017-07
- Description
-
Salmonella enterica is the leading cause of bacterial foodborne illness in the United States. In recent years, S. enterica has been frequently...
Show moreSalmonella enterica is the leading cause of bacterial foodborne illness in the United States. In recent years, S. enterica has been frequently linked to foodborne outbreaks associated with nuts and fruits; however, the underlying mechanisms of such association have not been fully understood. In the first part of this study, we evaluated the impact of various environmental factors and food surface attributes on the attachment and survival of five S. enterica strains representing serotypes Typhimurium, Enteritidis, Montevideo, Mbandanka, and Braenderup on three different raw nuts (i.e. black peppers, almonds and hazelnuts) and two different S. enterica strains including serotypes Typhimurium and Enteritidis on two fresh fruits (i.e. grape tomatoes and cantaloupes) under storage conditions relevant to industrial practice. We observed significant inter-strain variations in S. enterica survival on nut and fruit surface. A direct correlation was found between the nut and fruit surface roughness and S. enterica attachment and survival. Lower relative humidity (20%) and higher storage temperature (25oC) resulted in significant S. enterica reduction on nut shells. Lower storage temperature at 4oC significantly reduced S. enterica population on grape tomatoes. In the second part of this study, we used a newly-developed transposon mutagenesis library in S. enterica serotype Enteritidis genome and highthroughput sequencing analysis to identify genes with potential roles in S. enterica attachment to and survival on almonds and grape tomatoes. A total of 336 and 210 S. enterica genes displayed significant selection on almonds and grape tomatoes over a 7-d storage period at 25oC (p<0.05), respectively. Our results suggest that various food attributes, environmental factors as well as bacterial determinants collectively contribute to the survival and persistence of S. enterica on nuts and fruits, providing new data for future development of knowledge-based intervention strategies.
Ph.D. in Biology, July 2017
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- Title
- HIGH-FREQUENCY TRADING, LOW-FREQUENCY TRADING AND THE LIMIT ORDER MARKET
- Creator
- Li, Kun
- Date
- 2015, 2015-07
- Description
-
The emergence of High-Frequency Trading (HFT) has met with mixed reactions in both investment and academic communities. However, there still...
Show moreThe emergence of High-Frequency Trading (HFT) has met with mixed reactions in both investment and academic communities. However, there still exist gaps on distinguishing and interpreting the impact of HFT on the Low-Frequency Trading (LFT) side. In this thesis, I present three chapters that address the impact of HFT to LFT. I find evidence to distinguish trading generated by HFT in the limit order market, and consequently apply to explore how HFT affects LFT in terms of the liquidity and the order execution quality. In addition, I further explore the fleeting orders generated by HFT and their impact on the liquidity of LFT.
Ph.D. in Management Science, July 2015
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- Title
- DISTRIBUTED NOSQL STORAGE FOR EXTREME-SCALE SYSTEM SERVICES IN CLOUDS AND SUPERCOMPUTERS
- Creator
- Li, Tonglin
- Date
- 2015, 2015-12
- Description
-
As supercomputers gain more parallelism at exponential rates, the storage infrastructure performance is increasing at a significantly lower...
Show moreAs supercomputers gain more parallelism at exponential rates, the storage infrastructure performance is increasing at a significantly lower rate due to relatively centralized management. This implies that the data management and data flow between the storage and compute resources is becoming the new bottleneck for large-scale applications. Similarly, cloud based distributed systems introduce other challenges stemming from the dynamic nature of cloud applications. This dissertation addresses several challenges on storage systems at extreme scales for supercomputers and clouds by designing and implementing a zero-hop distributed NoSQL storage system (ZHT), which has been tuned for the requirements of high-end computing systems. ZHT aims to be a building block for scalable distributed systems. The goals of ZHT are delivering high availability, good fault tolerance, light-weight design, persistence, dynamic joins and leaves, high throughput, and low latencies, at extreme scales (millions of nodes). We have evaluated ZHT’s performance under a variety of systems, ranging from a Linux cluster with 64-nodes, an Amazon EC2 virtual cluster up to 96-nodes, to an IBM Blue Gene/P supercomputer with 8K-nodes. This work also presents several real systems that have adopted ZHT as well as other NoSQL systems, namely ZHT/Q, FusionFS, IStore, MATRIX, Slurm++, Fabriq, FREIDAState, and WaggleDB, all of these real systems have been significantly simplified due to NoSQL storage systems, and have been shown to outperform other leading systems by orders of magnitude in some cases. Through our work, we have shown how NoSQL storage systems can help on both performance and scalability at large scales in such a variety of environments.
Ph.D. in Computer Science, December 2015
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